Answer:
1 second
Explanation:
The impulse exerted on the boy is equal to its change of momentum:
where
F = 500 N is the push on the boy
is the contact time
m = 25 kg is the mass of the boy
is the change in velocity of the boy
Solving the formula for the contact time, we find
<span>No, there is no control group because each group is treated under test conditions.</span>
Explanation:
(c) I assume we're looking for mA.
Sum of forces on B in the -y direction:
∑F = ma
mBg − T = mBa
Sum of forces on A in the +x direction:
∑F = ma
T = mAa
Substitute:
mBg − mAa = mBa
mBg − mBa = mAa
mA = mB (g − a) / a
Plug in values:
mA = (5 kg) (10 m/s² − 0.01 (10 m/s²)) / (0.01 (10 m/s²))
mA = 495 kg
The answer key seems to have a mistake. It's possible they meant mB = 1 kg, or they changed mB to 5 kg but forgot to change the answer.
It’s a force which acts on an object without coming physically in contract with it.
