Answer:
Yes , insulation has no role
Answer:
v = 13.79 m/s
Explanation:
given,
mass of ball = 110 g
height = 11 m
ball is released from = 1.3 m
minimum speed = ?
using conservation of energy
Potential energy is conserved in the form of kinetic energy







v = 13.79 m/s
Answer:
A. The amount of mass changes only slightly during a chemical
reaction.
Let say the two train cars are of masses
and 
now if the speed of two cars are
and 
then we can say that the momentum of two cars before they collide is given by

here two cars are moving in opposite direction so we can say that the net momentum is subtraction of two cars momentum.
Now since in these two car motion there is no external force on them while they collide
So the momentum of two cars are always conserved.
hence we can say that the final momentum of two cars will be same after collision as it is before collision

The answer is "B".. Galileo discovered that dropping two items of the same mass, they can have different weights but no matter what the force that is acting upon them is the same amount, so this means that both objects will hit the ground at the same time. Galileo tested this theory and proved it right.