Answer A sounds about right
This being a perfect collision means no energy is lost during the collision. Because this question asks for speed and not velocity, the speed will be the same because the final energy is the same. The speed after the collision would therefore be 1.27 m/s.
Answer:
kinetic energy is the answer
Answer: A = 0.02 m²
Explanation: Solution:
Pressure is expressed in the formula:
P = F / A where F = mg
= mg /A
= 50 kg ( 9.8 m/s²) / 25000 Pa
= 0.02 m²
Answer:
Power = 377.35 W or Power = 0.5065 hp
Explanation:
Given:
Number of steps, n = 1576
height of each step, h = 0.20 m
Total height achieved, H = nh = 1576 × 0.20 = 315.2 m
Mass of the runner, M = 70.0 kg
Total time taken, t = 9 minutes 33 seconds = (9 × 60) + 33 = 573 seconds
Now, the potential energy gained by the runner,
E = MgH
where, g is the acceleration due to the gravity
on substituting the values in the above formula, we get
E = 70 × 9.8 × 315.2
or
E = 216227.2 J
also,
Energy = Power × time
therefore,
Power = Energy/time
or
Power = 216227.2 J / 573
or
Power = 377.35 W
Now,
745 watt = 1 hp
or
1 watt = 1/745 hp
thus,
Power = 377.35 W = 337.35 × (1/745) hp
or
Power = 0.5065 hp
