Two masses are attached to a rod end to end. If torque is applied they rotate with angular acceleration . If their distances are doubled and same torque is applied, then they move with angular acceleration
4 α
α
3 α
α/4
D.
α/4
Suppose the masses m1 and m2 are attached to the ends of a massless rod. C1 is the axis of rotation which is at a distance R from each of the masses.
∴ The moment of inertia of the system,
I = m1R2 + m2R2
I = ( m1 + m2 ) R2
Now if the distance between the masses is doubled, then the moment of inertia
I' = m1 ( 2R )2 + m2 ( 2R2 )
I' = ( m1 + m2 ) 4R2
Since the same torque torque is applied in both the cases.
τ = Iα = I' &alpha'
A particle is revolving in a circle of radius R. If the force acting on it is inversely proportional to R, then the time period is proportional to
R
R2
1/R
1/R2
If mass of an atom M moving with speed v, what will be its speed after the emission of an α-particle is zero?
A body of mass M moving with velocity V explodes into two equal parts. Id one comes to rest and the other moves with velocity v, what would be the value of v?
V
4V
2V
The orbital velocity of an artificial satellite in a circular orbit above the earth's surface at a distance equal to radius of earth is v. For a satellite orbiting at an altitude half of earth's radius, orbital velocity is
v
v
v
Maximum energy transfer for an elastic collision will occur if one body is at rest when
m1 = m2
m2 = m1
m1 >> m2
m2 >> m1
Escape velocity of a rocket is 11.2 km/sec. It is released at an angle of 45°. Its escape velocity is
11.2 m/sec
11.2 km/sec
11.2 km/sec
22.3 km/sec