Answer:
The answer is A.
Explanation:
The graph would show the unit rate otherwise known as a ratio
One way is to apply a surface the produces more friction (like sandpaper)
Answer: The height of rollercoaster cart above the ground is 1.53 m.
The velocity of rollercoaster cart is 5.29 m/s.
Explanation:
Potential energy is the energy occupied by a substance due to its position. Formula for potential energy is as follows.
P.E = mgh
where,
m = mass of substance
g = gravitational constant =
h = height
Substitute the values into above formula as follows.
Hence, the height of rollercoaster cart above the ground is 1.53 m.
Kinetic energy is the energy occupied by the motion of a substance. Formula for kinetic energy is as follows.
where,
m = mass of substance
v = velocity of substance
Substitute the values into above formula as follows.
Hence, the velocity of rollercoaster cart is 5.29 m/s.
Answer:
Explanation:
Modulus of elasticity of brick, Y = 28 x 10^9 Pa
mass of each, m = 40 kg
Area of each, A = 0.5 m²
number of bricks, n = 4
height, h = 5 m
Let the change in height is Δh.
Use the formula of Modulus of elasticity
E = stress/ strain
stress = n x m x g/A = 4 x 40 x 9.8 / 0.5 = 3136 Pa
So,
Δh = 5.6 x 10^-7 m
Answer: = 692.82Hz
Explanation: This question of ours is based on Doppler effect.The Doppler effect states that<em> if a source is producing sound at a specific frequency to an observer and there is a relative motion between the observer and the source, the frequency of sound perceived by the observer will be different from that of the original from the source. </em>
This represented mathematically below as
where
= observed frequency = ?
f = original frequency of sound source = 650Hz
v = speed of sound in air = 343m/s
= velocity of observer relative to the source = 0m/s ( the observer is standing, thus meaning he is not moving)
= velocity of sound source relative to the observer = 21.2m/s
by putting all of these in the formulae, we have that