Answer: (E) Momentum and mechanical energy
Explanation:
The momentum and the mechanical energy is basically conserved during the given interaction process as the forces on the given system are in the form of internal nature and then the momentum are get conserved.
According to the given question, on the smooth floor when an object are slides by using the spring then the momentum and the mechanical energy are conserved.
The mechanical energy is the combination of both the kinetic and the potential energy that is used for doing some amount of work. Therefore, Option (E) is correct answer.
Answer: 0.42 km/min
Explanation:
total distance traveled(in meters) = 210m
total distance traveled(in km) = 210 ÷ 1000 = 0.21 km
total time taken(in seconds) = 30 s
total time taken(in minutes) = 30 ÷ 60 = 0.5 s
speed =(distance traveled)÷(time taken)[in km/min] = 0.21 ÷ 0.5 = 0.42km/min
Answer:
0.06 A
Explanation:
We have given mass =0.954 kg
velocity =1.27 m/sec
efficiency =0.361 the output kinetic energy of the motor 
Efficiency =0.361
so input to the motor = output/efficiency
so input to the motor = 
we know that
where E is energy and T is time so 
We know that power P=VI we have given V=4.5 VOLT
So current 
The answer is it's middle the nueculs
Wow! Very simple. Use the equation for momentum which is p=mv. You know your momentum and velocity, so do 120=m(4), now solve for m, which is 30. The mass of the child is 30 kg