A small boy is playing with a ball on a stationary train. If he places the ball on the floor of the train, when the train starts moving the ball moves toward the back of the train. This happened due to inertia
An object at rest remains at rest, or if in motion, remains in motion unless a net external force acts on it .
When a train starts moving forward, the ball placed on the floor tends to fall backward is an example of inertia of rest. Due to the reason that the lower part of the ball is in contact with the surface and rest of the part is not . As the train starts moving, its lower part gets the motion as the floor starts moving but the upper part will remain as it is as it is not in contact with the floor , hence do not attain any motion due to the inertia of rest simultaneously i.e. it tends to remain at the same place.
To learn more about inertia here :
brainly.com/question/11049261
#SPJ1
Answer
given,
mass of the goalie(m₁) = 70 kg
mass of the puck (m₂)= 0.11 kg
velocity of the puck = 31.5 m/s
elastic collision







Answer:
The kinetic energy of the particle as it moves through point B is 7.9 J.
Explanation:
The kinetic energy of the particle is:
<u>Where</u>:
K: is the kinetic energy
: is the potential energy
q: is the particle's charge = 0.8 mC
ΔV: is the electric potential = 1.5 kV
Now, the kinetic energy of the particle as it moves through point B is:


Therefore, the kinetic energy of the particle as it moves through point B is 7.9 J.
I hope it helps you!
Answer:
Magnitude of force on wheel B is 4 N
Explanation:
Given that

For wheel A
m= 1 kg
d= 1 m,r= 0.5 m
F=1 N
We know that
T= F x r
T=1 x 0.5 N.m
T= 0.5 N.m
T= I α
Where I is the moment of inertia and α is the angular acceleration


T= I α
0.5= 0.25 α

For Wheel B
m= 1 kg
d= 2 m,r=1 m


Given that angular acceleration is same for both the wheel

T= I α
T= 1 x 2
T= 2 N.m
Lets force on wheel is F then
T = F x r
2 = F x 1
So F= 2 N
Magnitude of force on wheel B is 2 N
Answer:
v = 79.2 m/s
Solution:
As per the question:
Mass of the object, m = 250 g = 0.250 kg
Angle, 
Coefficient of kinetic friction, 
Mass attached to the string, m = 0.200 kg
Distance, d = 30 cm = 0.03 m
Now,
The tension in the string is given by:
(1)
Also
T = m(g + a)
Thus eqn (1) can be written as:





Now, the speed is given by the third eqn of motion with initial velocity being zero:

where
u = initial velocity = 0
Thus

