Answer:
6.26 m/s
Explanation:
Pretty slow.... the PE (Potential Energy) at 2m will be converted to KE (Kinetic Energy) at the bottom of the track (neglecting friction)
PE = KE
mgh = 1/2 mv^2 divide both sides of the equation by 'm'
gh = 1/2 v^2 multiply both sides by 2
2 gh = v^2 take sqrt of both sides
v = sqrt ( 2gh) = sqrt ( 2*9.81*2) = 6.26 m/s
Answer:
Increasing until terminal velocity is reached
Explanation:
Provided the scream is a constant pitch at the source, Doppler effect will make the pitch increase as the velocity of the source towards the listener increases.
Answer:
The number of crates is 84580.
Explanation:
mass, m = 30 kg
height, h = 0.9 mm
Power, P = 0.5 hp = 0.5 x 746 W = 373 W
time, t = 1 minute = 60 s
Let the number of crates is n.
Power is given by the rate of doing work.
![P = \frac{n m gh}{t}\\\373 =\frac{n\times 30\times9.8\times 0.9\times 10^{-3}}{60}\\\\n =84580](https://tex.z-dn.net/?f=P%20%3D%20%5Cfrac%7Bn%20m%20gh%7D%7Bt%7D%5C%5C%5C373%20%3D%5Cfrac%7Bn%5Ctimes%2030%5Ctimes9.8%5Ctimes%200.9%5Ctimes%2010%5E%7B-3%7D%7D%7B60%7D%5C%5C%5C%5Cn%20%3D84580)
Answer: Instantaneous speed.
Explanation: