Answer:
Explanation:
Horizontal component of initial velocity of throw = 20 cos 53 = 12 m /s
Vertical component = 20 sin 53 = 15.97 m /s
Distance to be travelled horizontally = 6 m .
time taken by ball to travel this distance = 6 / 12 = 0.5 s
vertical displacement during this period can be calculated as follows .
Initial vertical velocity = 15.97 m /s
time of travel = .5 s
acceleration = - 9.8 m /s²
s = ut - 1/2 g t²
= 15.97 x .5 - .5 x 9.8 x 0.5²
= 7.985 - 1.225
= 6.76 m
Goal post is 6 m high , so ball will cross the goal post .76 m or 76 cm above cross bar .
b ) vertical component of ball when it crosses the goal post . Let it be v .
v = u - gt
Applying this formula for vertical movement ,
v = 15.97 - 9.8 x .5
= 15.97 - 4.9
= 11.07 m /s .
As an electromagnetic wave travels, what is the relationship between the
magnetic field and the electric field along its path?
A. They are parallel to each other.
B. The angle between them decreases with an increase in energy
O C. The angle between them increases with an increase in energy.
D. They are at a 90° angle to each other.
Answer:
Its D
Explanation:
They are at a 90° angle to each other.
Do good on your tests :]
The answer is D) They are at a 90° angle to each other.
What is an electromagnetic wave?One of the waves which are propagated with the aid of simultaneous periodic versions of electrical and magnetic subject depth and consists of radio waves, infrared, seen mild, ultraviolet, X-rays, and gamma rays.
Radio waves, microwaves, seen light, and x-rays are all examples of electromagnetic waves that range very differently in wavelength. (a) Longer wavelength; (b) shorter wavelength. Electromagnetic waves are produced by means of the motion of electrically charged debris.
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1. li took 2 } seconds for a car's vclocity to change from 20 m/s to 15 m/s. The mass of the car was 1370 kg. What force was required to cause the acceleration? (Hint: First calculate the acceleration.
Answer:
Do you still need help??
Explanation:
Hi everyone.
How are you all I hope you guys are fine.
question:why the symbol of Joule is capital (J)?
Answer:
The joule (symbol: J) is the basic SI unit of energy. A joule is equal to the kinetic energy of a kilogram mass moving at the speed of one meter per second (one joule is a kg⋅m2⋅s−2). ... Because it is named for a person, the first letter of the symbol is uppercase (J instead of j)
Explanation:
I have a massive rock weighing 3,000 Newtons but I can only accelerate it to 500 m/s2 what is its mass?
Answer:
6 kg
Explanation:
F=ma
F is Force(newtons)
m is mass(kg)
a is acceleration(m/s^2)
Plug in the numbers
3000 = m(500)
divide both sides by 500 to cancel out the 500.
3000/500=6
6 = m
6kg is the mass
A swimmer, capable of swimming at a speed of 1.60 m/s in still water (i.e., the swimmer can swim with a speed of 1.60 m/s relative to the water), starts to swim directly across a 1.25-km-wide river. However, the current is 0.549 m/s, and it carries the swimmer downstream. (a) How long does it take the swimmer to cross the river
Answer:
t = 781.25 s
Explanation:
This is an exercise in velocity composition, if we set a reference system where the x-axis is perpendicular to the river and the y-axis is parallel to the river.
The swimmer has a velocity on the x axis
vx = 1.60 m / s
a velocity on the y axis, created by the current of the river
vy = 0.549 m / s
time is a scalar, therefore the time it takes to cross the river is the same time it creates the displacement in e; Axis y
X axis
vₓ = x / t
t = x / vₓ
t = 1250 / 1.6
t = 781.25 s
in this time a distance has descended
y = v_y t
y = 0.549 781.25
y = 428.9 m
What does Fgrav or Fg mean when its next to a vector arrow?
A wheelbarrow is pushed 10 meters with a force of 75 N for 30 seconds. What is the work done?
How much power is needed?
What is the average speed of a car that travels 60 meters in 2
seconds?
Answer:
30 m/s
Explanation:
Speed is distance over time. 60 meters / 2 seconds, = 30 m/s.
I love buying physics toys. I recently broke out my new electromagnetic field meter and started playing with it. After turning it on, I noticed the device kept showing an electric field value of 200 N/C towards the ground, without being near anything obvious (e.g., an electronic device) that would be producing the electric field. I even took a long walk to check if the reading was somehow localized to my house, but I got the same result. How might you explain the reading (assuming the device is working properly)
Answer:
ionized particles from the sun.
* interactions in radiation belts.
* the friction of the planet in the solar wind
q = +9 10⁵ C
Explanation:
Due to being made up of matter, the planet Earth has a series of positive and negative charges, in general these charges should be balanced and the net charge of the planet should be zero, but there are several phenomena that introduce unbalanced charges, for example:
* ionized particles from the sun.
* interactions in radiation belts.
* the friction of the planet in the solar wind
This creates that the planet has a net electrical load
We can roughly calculate the charge of the planet
E = k q / r²
q = E r² / k
let's calculate
q = 200 (6.37 10⁶)²/9 10⁹
q = +9 10⁵ C
6 An object can never have
A. a positive speed.
B. a negative speed.
C. a positive velocity.
D. a negative velocity.
Answer:
B
Explanation:
Speed is the magnitude of the velocity vector, so it can never be negative.
An object can never have a negative velocity. Therefore, option (D) is correct.
What is velocity?Velocity is a vector quantity that describes an object's speed and direction of motion. If an object is moving in a positive direction, it has a positive velocity. If it is moving in the opposite direction, it has a negative velocity.
However, an object can never have a negative speed. Speed is a scalar quantity that describes an object's rate of motion, and it is always positive. The speed of an object can be positive or negative, depending on the direction of its velocity, but the magnitude of its speed is always positive.
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Based on your graph, predict the length of pendulum that will give you a
period of 2.00s.
Answer:
About 1 meter
Explanation:
Base on your image, when the period is 2 (horizontal variable), the length of the pendulum is about 1 meter.
INT Raindrops acquire an electric charge as they fall. Suppose a 2.0-mm-diameter drop has a charge of 12 pC; these are both very common values. In a thunderstorm, the electric field under a cloud can reach 15,000 N/C, directed upward. For a droplet exposed to this field, how do the magnitude and direction of the electric force compare to those of the weight force
Answer:
W = 2.3 10² [tex]F_{e}[/tex]
Explanation:
The force of the weight is
W = m g
let's use the concept of density
ρ= m / v
the volume of a sphere is
V = [tex]\frac{4}{3}[/tex] π r³
V = [tex]\frac{4}{3}[/tex] π (1.0 10⁻³)³
V = 4.1887 10⁻⁹ m³
the density of water ρ = 1000 kg / m³
m = ρ V
m = 1000 4.1887 10⁻⁹
m = 4.1887 10⁻⁶ kg
therefore the out of gravity is
W = 4.1887 10⁻⁶ 9.8
W = 41.05 10⁻⁶ N
now let's look for the electric force
F_e = q E
F_e = 12 10⁻¹² 15000
F_e = 1.8 10⁻⁷ N
the relationship between these two quantities is
[tex]\frac{W}{F_e}[/tex] = 41.05 10⁻⁶ / 1.8 10⁻⁷
\frac{W}{F_e} = 2,281 10²
W = 2.3 10² [tex]F_{e}[/tex]
therefore the weight of the drop is much greater than the electric force
The electric potential inside a living cell is lower than the potential outside. Suppose the electric potential difference between the inner and the outer cell wall is 0.095 V, a typical value. To maintain the internal electrical balance, the cell pumps out sodium ions. How much work must be done to remove a single sodium ion (charge e)
Answer:
1.52 × 10⁻²⁰ J
Explanation:
The electrical potential difference is defined as the amount of work done in carrying a unit charge from one point to another point in an electric field. Electric potential difference is measured in volts. It is given by the formula:
ΔV = ΔU / q
ΔV is electric potential difference between the two points, ΔU is the work done and q is the unit charge.
Given that ΔV = 0.095 V, q = 1.6 × 10⁻¹⁹ C. Hence:
ΔU = ΔV.q
ΔU = 0.095 V * 1.6 × 10⁻¹⁹ C
ΔU = 1.52 × 10⁻²⁰ J
The electric potential difference is the amount of effort done in an electrical field to shift a unit charge from one spot to another.The electric potential difference will be 1.52×10⁻²⁰J.
What is the electric potential difference ?
The electrical potential difference is the amount of effort done in an electrical field to shift a unit charge from one spot to another.
Traditional current flows from positive to negative terminals, signifying positive charge transfer in that direction.
The given data in the problem is
[tex]\triangle V[/tex] is the electric potential difference between the inner and the outer cell wall = 0.095 V
[tex]\triangle U[/tex] is the amount of work done
q is the charge on the electron =1.6×10⁻¹⁹C
Electric potential difference is given by the formula
[tex]\triangle V=\frac{\triangle U}{q} \\\\ \triangle U=\triangle Vq\\\\\triangle U=0.095 V\times1.6\times10^{-19}\\\\ \triangle U=1.52\times10^{-20}J[/tex]
Hence the electric potential difference will be 1.52×10⁻²⁰J.
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please help me out with these !! 50 points would greatly appreciate it.
Answer:
Its nymber 2
Explanation:
The design of interior spaces is relatively unimportant to good
architecture?
is
5
The specific heat of copper is 0.385 J/g
°C. How much thermal energy is required
to increase the temperature of a 20g
sample of copper from 20°C to 50°C?
Q = m CAT
A 154 )
B 231 )
C 308 )
D 385 )
Answer:
Required energy Q = 231 J
Explanation:
Given:
Specific heat of copper C = 0.385 J/g°C
Mass m = 20 g
ΔT = (50 - 20)°C = 30 °C
Find:
Required energy
Computation:
Q = mCΔT
Q = 20(0.385)(30)
Required energy Q = 231 J
Suppose you had 10 identical molecules enclosed by a box. At a given instant, one molecule has an energy of 100 Joules, and the others are all stationary. (A) What is the average kinetic energy of the 10 molecules
Answer:
the average kinetic energy of the 10 molecules is 10 J.
Explanation:
Given;
energy on one molecule in motion, E = 100 J
number of molecules, n = 10
(A) The average kinetic energy of the 10 molecules
since the remaining 9 molecules are at rest, their kinetic energy = 0
[tex]E_{Avg} = \frac{E_1 + E_9}{10} \\\\E_{Avg} = \frac{100J+ 0}{10} \\\\E_{Avg} = \frac{100J}{10} \\\\E_{Avg} = 10J[/tex]
Therefore, the average kinetic energy of the 10 molecules is 10 J.
True or False:
Some stars appear dimmer than others. Dim stars are always further
away from us than bright stars.
Answer:
A star's brightness also depends on its proximity to us. The more distant an object is, the dimmer it appears.
At the instant the traffic light turns green, an automobile starts with a constant acceleration a of 2.70 m/s2. At the same instant a truck, traveling with a constant speed of 9.50 m/s, overtakes and passes the automobile. (a) How far beyond the traffic signal will the automobile overtake the truck
Answer:
66.85 m
Explanation:
We are given that
Acceleration ,a=[tex]2.7m/s^2[/tex]
Speed of truck, v=9.5 m/s
We have to find the distance beyond which the traffic signal will the automobile overtake the truck.
Initial speed of automobile, u=0
We know that
[tex]s=ut+\frac{1}{2}at^2[/tex]
Using the formula
[tex]s=0+\frac{1}{2}(27)t^2=\frac{27}{2}t^2[/tex]
For constant speed
Acceleration, a=0
Again
[tex]s=vt+0=9.5t[/tex]
[tex]9.5t=\frac{27}{2}t^2[/tex]
[tex]t=\frac{9.5\times 2}{2.7}=7.037s[/tex]
Substitute the value of t
[tex]x=9.5(7.037)=66.85m[/tex]
Hence, the distance beyond which the traffic signal will the automobile overtake the truck=66.85 m
Can someone please help, ty!!
Will mark brainliest.
Answer:
#1 ( Balanced ) ( Rest)
#2 ( Unbalanced) ( Accelerating)
Explanation:
Based on the data, which statement describes the most reliable way to
encode and transmit data and tells why?
A. Digital waves are more reliable because they are less likely to
change when copied.
B. Analog waves are more reliable because they include a range of
values like the original.
C. Analog waves are more reliable because they are less likely to
change when copied.
D. Digital waves are more reliable because they are slightly different
from the original.
Answer:it’s A. right for ape x
Explanation:
Based on data, digital waves are more reliable because they are less likely to change when copied (Option A).
What is a wave?A wave is a periodic distortion capable of traveling through a suitable media (either air or water).
The waves can be classified according to their direction into transversal and perpendicular.In conclusion, based on data, digital waves are more reliable because they are less likely to change when copied (Option A).
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A body moves on a coordinate line such that it has a position sequalsf(t)equalstsquaredminus4tplus3on the interval 0less than or equalstless than or equals7,with s in meters and t in seconds.a. Find the body's displacement and average velocity for the given time interval.b. Find the body's speed and acceleration at the endpoints of the interval.c. When, if ever, during the interval does the body change direction?
Answer:
A) Δf = - 49 m, B) v (7) = -56 m / s, a = - 8 m / s², C) t = 0.866 s
Explanation:
A) In this exercise ask to find the displacement and the average velocity, give the function of the movement
f (t) = - 4t² +3
and the range of motion 0≤ t ≤ 7
the displacement is
for t = 0
f (0) = 3
for t = 7 s
f (7) = - 4 7² +3
f (7) = -46 m
the total displacement is
Δf = f (7) - f (0)
Δf = -46 - 3
Δf = - 49 m
the average speed is defined as the displacement between the time interval
v = Df / Dt
v = -49 / 7
v = - 7 m / s
B) the speed and acceleration of the end points of the motion
the speed of defined by
v = [tex]\frac{dx}{dt}[/tex]
in this case
v = [tex]\frac{df}{dt}[/tex]
v = -8t
let's calculate
v (7) = -8 7
v (7) = -56 m / s
acceleration is defined by
a = [tex]\frac{dv}{dt}[/tex]
a = - 8 m / s²
acceleration is constant throughout the movement
C) the point where the direction changes.
This point is a point where the position goes from positive to negative, the point f = 0
0 = -4t² +3
t = √¾
t = 0.866 s
1 example of a conductor and 1 example of a insulator in your EVERYDAY world.
Answer: Examples of conductors include metals, aqueous solutions of salts (i.e., ionic compounds dissolved in water), graphite, and the human body. Examples of insulators include plastics, Styrofoam, paper, rubber, glass and dry air.
Starting from the front door of your ranch house, you walk 55.0 mm due east to your windmill, turn around, and then slowly walk 40.0 mm west to a bench, where you sit and watch the sunrise. It takes you 25.0 ss to walk from your house to the windmill and then 37.0 ss to walk from the windmill to the bench.
Required:
a. For the entire trip from your front door to the bench, what is your average velocity?
b. For the entire trip from your front door to the bench, what is your average speed?
Answer:
a) V = 0.24 m/s
b) v = 1.53 m/s
Explanation:
In this case, we are asked to find two values that are pretty similar and use the same units, however, there are differences between them.
The average velocity is often referred to a vector quantity, therefore, if time is a scalar magnitude, we need to find the vector quantity of distance. In this case, is the displacement, which is also referred as a vector.
So, to calculate the average velocity we need to determine first the displacement of the person. As the person heads east and then west, his total displacement (D) is:
D = 55 - 40 = 15 m
Now the total time would be the time taken to go to the windmill and then, to a bench:
t = 25 + 37 = 62 s
Finally, the average speed is:
V = D/t
V = 15 / 62
V = 0.24 m/sThe average speed is a scalar magnitude, so we use the covered distance by the person (d) and the total time:
d = 40 + 55 = 95 m
Then, the speed:
v = 95/62
v = 1.53 m/sHope this helps
Two children, Ferdinand and Isabella, are playing with a water hose on a sunny summer day. Isabella is holding the hose in her hand 1.0 meters above the ground and is trying to spray Ferdinand, who is standing 10.0 meters away. Will Isabella be able to spray Ferdinand if the water is flowing out of the hose at a constant speed v0 of 3.5 meters per second?
Answer:
Isabella will not be able to spray Ferdinand.
Explanation:
We'll begin by calculating the time taken for the water to get to the ground from the hose held at 1 m above the ground. This can be obtained as follow:
Height (h) = 1 m
Acceleration due to gravity (g) = 9.8 m/s²
Time (t) =.?
h = ½gt²
1 = ½ × 9.8 × t²
1 = 4.9 × t²
Divide both side by 4.9
t² = 1/4.9
Take the square root of both side
t = √(1/4.9)
t = 0.45 s
Next, we shall determine the horizontal distance travelled by the water. This can be obtained as follow:
Horizontal velocity (u) = 3.5 m/s
Time (t) = 0.45 s
Horizontal distance (s) =?
s = ut
s = 3.5 × 0.45
s = 1.58 m
Finally, we shall compare the distance travelled by the water and the position to which Ferdinand is located to see if they are the same or not. This is illustrated below:
Ferdinand's position = 10 m
Distance travelled by the water = 1.58 m
From the above, we can see that the position of the water (i.e 1.58 m) and that of Ferdinand (i.e 10 m) are not the same. Thus, Isabella will not be able to spray Ferdinand.
Which is the weakest of the four fundamental forces?
strong nuclear
weak nuclear
electromagnetic
gravitational
Answer:
Gravitational
Explanation:
gravitational
Answer:
Gravitational
Explanation:
In order from strongest to weakest.
Strong nuclear
Electromagnetic
Weak nuclear
Gravitational
Suppose a cat climbs a tree to a height of 2 meters. If the cat doubles its height to 4 meters, its potential energy will
1)not change
2)reduce to halve
3)double
4)quadruple
A body is dropped from the roof of a 20 m high building by how much:
Does it take to reach the ground? How fast does it hit the ground?
Answer:
t = 2.01 s
Vf = 19.7 m/s
Explanation:
It's know through the International System that the earth's gravity is 9.8 m/s², then we have;
Data:
Height (h) = 20 mGravity (g) = 9.8 m/s²Time (t) = ?Final Velocity (Vf) = ?==================================================================
Time
Use formula:
[tex]\boxed{t=\sqrt{\frac{2*h}{g}}}[/tex]Replace:
[tex]\boxed{t=\sqrt{\frac{2*20m}{9.8\frac{m}{s^{2}}}}}[/tex]Everything inside the root is solved first. So, we solve the multiplication of the numerator:
[tex]\boxed{t=\sqrt{\frac{40m}{9.8\frac{m}{s^{2}}}}}[/tex]It divides:
[tex]\boxed{t=\sqrt{4.08s}}[/tex]The square root is performed:
[tex]\boxed{t=2.01s}[/tex]==================================================================
Final Velocity
use formula:
Vf = g * tReplace:
Vf = 9.8 m/s² * 2.01 sMultiply:
Vf = 19.7 m/s==================================================================
How long does it take to reach the ground?
Takes time to reach the ground in 2.01 seconds.
How fast does it hit the ground?
Hits the ground with a speed of 19.7 meters per seconds.
Postural deviations can result in
Answer:
Postural deviations can cause poor balance, muscle pain and skeletal stress.
Explanation:
The mass percent of hydrogen in CH₄O is 12.5%.
What is the mass percent?Mass percent is the mass of the element divided by the mass of the compound or solute.
Step 1: Calculate the mass of the compound.
mCH₄O = 1 mC + 4 mH + 1 mO = 1 (12.01 amu) + 4 (1.00 amu) + 1 (16.00 amu) = 32.01 amu
Step 2: Calculate the mass of hydrogen in the compound.
mH in mCH₄O = 4 mH = 4 (1.00 amu) = 4.00 amu
Step 3: Calculate the mass percent of hydrogen in the compound.
%H = (mH in mCH₄O / mCH₄O) × 100%
%H = 4.00 amu / 32.01 amu × 100% = 12.5%
The mass percent of hydrogen in CH₄O is 12.5%.
CO2 = 1.580 grams H2O = 0.592 grams Lookup the molar mass of each element in the compound Carbon = 12.0107 Hydrogen = 1.00794 Oxygen = 15.999 Calculate the molar mass of CH4O by adding the total masses of each element used. 12.0107 + 4 * 1.00794 + 15.999 = 32.04146 Now calculate how many moles of CH4O you have by dividing by the molar mass. m = 1.15 g / 32.04146 g/mole = 0.035891 mole Now figure out how many moles of carbon and hydrogen you have. Carbon = 0.035891 moles Hydrogen = 0.035891 moles *
Therefore, The mass percent of hydrogen in CH₄O is 12.5%.
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Peter, a 100 kg basketball player, lands on his feet after completing a slam dunk and then immediately jumps up again to celebrate his basket. When his feet first touch the floor after the dunk, his velocity is 5 m/s downward; when his feet leave the floor 0.50 s later, as he jumps back up, his velocity is 4 m/s upward. a. What is the impulse exerted on Peter during this 0.50 s
Answer:
Explanation:
Impulse = change in momentum
Initial momentum = mass x initial velocity = 100 x 5 = 500 kg m/s
final momentum = mass x final velocity = 100 x - 4 = -400 ( - ve sign due to reversal of direction )
change in momentum = final momentum - initial momentum
= - 400 - 500 = - 900 kg m/s .
As it is - ve , it acts upwards .
So magnitude of impulse on Perter = 900 kg m/s
