Bob gained (80lbs x 14ft) = 1120 ft-lbs of energy.
Fred gained (110lbs x 14ft) = 1540 ft-lbs of energy
Since they both took the same amount of time, Fred's power (rate
of doing work) was greater than Bob's power (rate of doing work).
Answer:
Explanation:
When a person shouts it emits 1 W of energy as sound waves, P = 1 W
Let I is the sound intensity 1 meters from such a person. We know that the power per unit area is called the sound intensity of the person. Its formula is given by :
So, the sound intensity of such a person is 
. Hence, this is the required solution.
Answer:
If the weight and forces are the same, it will result in a balance, i they are different, it will result in an overload in the lower force/mass object, reflecting it to the opposite direction with higher speed.
Explanation:
We can find the force by using the following formula;
N = ma + mg
Fa = ma = 76 x 1.2 = 91.2
Fg = mg = 76 x 9.8 = 744.8
N = 91.2 + 744.8 = 836
So, the force is 836 N.
Answer: (C) Slide against each other
Explanation:
Think about rubbing our palms together, and they get warm that right there is friction.
