Answer:
option d) -9 J
Explanation:
Given:
Mass, m = 3.0 kg
time, t = 6.0 seconds
Velocity of mass, v = 2.0 m/s
height, h = 2 m
Now, using the concept of work-Energy theorem
we have
Net work done = change in kinetic energy
or
Work done by gravity + work done by the friction = Final kinetic energy - Initial kinetic energy
mgh +
= 
on substituting the values in the above equation, we get
3 × 9.8 × 2 + = 
or
58.8 + = 6
or
= -52.8 J
here negative sign depicts that the work is done against the motion of the mass
also,
Power = (Work done)/time
or
Power = -52.8/6 = -8.8 W ≈ 9 J
Hence, option d) -9 J is correct
The momentum of each vehicle is (its mass) times (its speed).
Answer:
hey from what I know the answer is C
Explanation:
When a book is kept on a table , weight (gravitational force) of book acts on table vertically downwards and as a reaction of weight , table also exerts an equal and opposite ( upward) force on book .
Infrasound sound is any sound that are below the sound a human can hear, elephants use it to communicate with other elephants.
Leave them, listen you are better than being with someone who is unsure. If you are 100% in this they need to match the energy. The purpose of dating is going into marriage eventually and imagine if when you get married they are like “wait I don’t know actually”. True me dump them and don’t look back
