A sphere rolls down an inclined plane of inclination θ. What is the acceleration as the sphere reaches the bottom?
In a bicycle, the radius of rear wheel is twice the radius of front wheel. If rf and rr are the radii, vf and vr are the speeds of topmost points of the wheel, then:
vr = 2vf
vf = 2vr
vr = vf
vf > vr
Moment of inertia of an object does not depend upon :
mass of the object
mass distribution
angular velocity
axis of rotation
A particle falls towards earth from infinity. Its velocity on reaching the earth would be:
infinity
zero
Two bodies of mass m and 4m have equal kinetic energy. What is the ratio of their momentum?
1 : 4
1 : 2
1 : 1
2 : 1
According to Kepler's law, the time period of a satellite varies with its radius are as:
T2 ∝ R3
T3 ∝ R2
A particle is moving in a circle with uniform speed v. In moving from a point to another diametrically opposite point :
the momentum changes by mv
the momentum changes by 2mv
the kinetic energy changes by 1/2 mv2
the kinetic energy changes by mv2
B.
the momentum changes by 2mv
Initial velocity v1 = v
Final velocity v2 = -v
Initial momentum p1 = mv
Final momentum p= m (-v) = - mv
Change in momentum
Δp = p1 - p2
= mv - (-mv)
= 2mv
The radius R of the soap bubble is doubled under isothermal condition. If T be the surface tension of soap bubble, the required surface energy in doing so is given by:
32πR2T
24πR2T
8πR2T
4πR2T
Mercury boils at 367°C. However, mercury thermometers are made such that they can measure temperature upto 500°C. This is done by:
maintaining vacuum above the mercury column in the stem of the thermometer
filling nitrogen gas at high pressure above the mercury column
filling oxygen gas at high pressure above the mercury column
filling nitrogen gas at low pressure above the mercury column
An ice-cube of density 900 kg/m3 is floating in the water of density 1000 kg/m3 The percentage of volume of the ice-cube outside the water is:
20 %
35 %
10 %
25 %