Cars 'A' and 'C' look like they're moving at the same speed. If their tracks are parallel, then they're also moving with the same velocity.
There is still air inside of a house, which is pushing the roof upwards, so the forces are equal and the roof is not crushed.
W=gm
where g - gravitation
m - mass
w - weight
as gravitation equals to zero, multiplying by 0 gives W=0
It is not possible to tell whether and object is heavy or light
Momentum is conserved if and only if sum of all forces which are exserted on system equals zero. In our situation there are only internal forces, so by Newton's third law their vector sum is 0.
So
.
Kinetic energy of system at first:
. After:
. The secret is that other energy is in work of deformation forces (they in turn heat a bullet and a block).
Answer is A)
Answer:
The taken is 
Explanation:
Frm the question we are told that
The speed of car A is 
The speed of car B is 
The distance of car B from A is 
The acceleration of car A is 
For A to overtake B
The distance traveled by car B = The distance traveled by car A - 300m
Now the this distance traveled by car B before it is overtaken by A is

Where
is the time taken by car B
Now this can also be represented as using equation of motion as

Now substituting values

Equating the both d

substituting values




Solving this using quadratic formula we have that
