Velocity = distance /time
acceleration = velocity / time
Red light would be commonly used due to the longer wavelength
Answer:
(E)56.0 m/s
Explanation:
Height =h=-160 m
Because the wallet moving in downward direction
Time=t=7 s
Final speed of wallet=v=0
We have to find the speed of helicopter ascending at the moment when the passenger let go of the wallet.

Where 
Substitute the values



Option (E) is true
Answer:
<em>K =400000 J</em>
Explanation:
<u>Kinetic Energy</u>
Is the energy an object has due to its state of motion. It's proportional to the square of the speed.
The equation for the kinetic energy is:

Where:
m = mass of the object
v = speed at which the object moves
The kinetic energy is expressed in Joules (J)
The car has a mass of m=2000 Kg and travels at v=20 m/s. Calculating the kinetic energy:

Calculating:
K =400000 J