Answer:
This is due to impulse
Explanation:
Impulse equal to mΔv and FΔt
You can set these equal as mΔv = FΔt
When a boxer punches a tissue, it is like punching a cushion or a pillow. The time that the hit takes is much grater than if they were to hit something solid. In addition, the change in velocity of the boxer's arm would be much greater when they hit a punching bag. In this equation, the greater the time, the less force that is needed.
Is balancing .
Hope this is helpful
Answer:
Explanation:
s = s₀ + v₀t + ½at²
s = 0 + 0(15) + ½(6)(15²)
s = 675 m
Not sure what the free fall acceleration is needed for, but if the object is dropped from a high enough point, it will travel in 15 seconds
s = ½10(15²) = 2250 m if air resistance is ignored
Answer:
Approximately 
, assuming that the acceleration of this ball is constant during the descent.
Explanation:
Assume that the acceleration of this ball, 
, is constant during the entire descent.
Let 
denote the displacement of this ball and let 
denote the duration of the descent. The SUVAT equation 
would apply.
Rearrange this equation to find an expression for the acceleration, , of this ball:
.
Note that 
and 
in this question. Thus:
.
Let 
denote the mass of this ball. By Newton's Second Law of Motion, if the acceleration of this ball is , the net external force on this ball would be 
.
Since 
and 
, the net external force on this ball would be:
.
Answer:
0.96 kWh
Explanation:
First of all, we can find the power of the appliance using the formula:
where
V = 120 V is the voltage of the source
I = 2 A is the current
Substituting,
Now we want to find the amount of energy used by the applied in a time of
t = 4 h
The amount of energy is given by
where
P = 0.24 kW
t = 4 g
Substituting,
