Answer:25 N
Explanation:
Given
mass of 5 , 3 & 2 kg blocks lie on floor
Force on 50 N pushes the 5 kg box
be the reaction on 2 kg box therefore

where a is the acceleration of the system
reaction on 3 kg block by 5 kg block


Now for 5 kg block

F=10a

Force exerted by 5 kg block on 3 kg block is

Question:
How do rechargeable batteries work?
Answer:
When a rechargeable battery is connected to electricity it changes the pressure inside and allows the rubber membrane to expand, thus releasing more energy next time its used. When plugged into the wall the electrons are sent back to rebuild the original dry cell (or metal). Rechargeable batteries are made exclusively of nitrogen which when exposed to electricity from and outlet can store a charge. When a battery is zapped by the electricity from the outlet it resets the system.
Answer:

Explanation:
The kinetic energy of an object is given by
where
is the mass of the object and
is the velocity of the object.
We can set up the following equations with the information given:

For part B, we have the same equation, but kinetic energy is now
.
Therefore:
.
42) The sailboat travels east with velocity

, while the current moves south with speed

. Since the two velocities are perpendicular to each other, he resultant velocity will be given by the Pytagorean theorem:

and the direction is in between the two original directions, therefore south-east. So, the correct answer is
D) 42 mph southeast
43) Since the light moves by uniform motion, we can calculate the distance corresponding to one light year by using the basic relationship between velocity, space and time. In fact, we know the velocity:

and the time is one year, corresponding to:

therefore, the distance corresponding to one light year is:

Therefore, the correct answer is D.
44) For the purpose of the problem, we can assume that the light travels instantaneously from the flash to us (because the distances involved are very small), so the time between the flash and the thunder corresponds to the time it took for the sound to travel to us.
The speed of sound is

And since the time between the flash and the thunder is t=3 s, the distance is

Therefore, the correct answer is A) 3/5 mile.