1) Assuming an adult person has an average mass of m=80 kg, and assuming it takes about 30 seconds to climb 5 meters of stairs, the energy used by the person is

So the power output is

And since the estimate we made is very rough, we can say that the power output of the person is comparable to the power output of the light bulb of 100 W.
2) Based on the results we found in the previous part of the exercise, since the power output of the person is comparable to the power output of 1 light bulb of 100 W, we can say that the person could have kept burning only one 100-W light bulb during the climb.
It’s frequency is high and microwaves can pass through the atmosphere of the Earth.
Answer:
Explanation:
Given
mass of steel ball 
initial speed of ball 
Final speed of ball
(in upward direction)
Impulse imparted is given by change in the momentum of object
therefore impulse J is given by




so magnitude of Impulse =4 N-s
C. Eastward. Acceleration is the change in speed so it can be a positive (speeding up) or negative (slowing down) acceleration
Use the Pythagoras for the magnitude and the tan^-1 x = -1 for the angle
displacement = 4^2 + 4^2 = 32 = 4 sqrt(2) = 5.65 km
angle is 135 degrees.