Answer: initial velocity of bullet = 50.72m/s
Explanation:
Detailed explanation and calculation is shown in the image below.
NB: the wooden block has an initial velocity u = 0 since it was at rest.
Answer:
The mechanical advantage of using a lever is affected by the distance between the effort and the fulcrum and by the placement of the load. ... When the fulcrum is centered between the load and the lift, the amount of effort exerted to push down on the lever equals the amount of the load being lifted on the other end.
The distance the object moved is 100 m
the power of the machine is 1000 watts
distance = work/force (because work = force x distance)
distance = 20000/200 = 100
power = work/ time
power = 20000/20 = 1000
Question: Two people stand facing each other at a roller-skating rink then push off each other. If the girl skater has a mass of 30 kg and moves backward at 5 m/s, what is the velocity of the boy skater if his mass is 50 kg?
Answer:
3 m/s
Explanation:
Applying,
The Law of conservation of momentum
Momentum of the girl skater = momentum of the boy skater
MV = mv...................... Equation 1
Where M = mass of the girl skater, V = velocity of the girl skater, m = mass of the boy skater, v = velocity of the boy skater
From the question, we were asked to calculate v
v = MV/m.................. Equation 1
Given: M = 30 kg, V = 5 m/s, m = 50 kg
Substitute these values into equation 1
v = (30×5)/50
v = 3 m/s
Hence the velocity of the the boy skater is 3m/s
