CBSE
Multiple Choice QuestionsTwo particles are seen to collide and move jointly together after the collision. During such a collision, for the total system.
both the mechanical energy and the linear momentum are conserved
linear momentum is conserved but not the mechanical energy
neither the mechanical energy nor the linear momentum is conserved
mechanical energy is conserved but not the linear momentum
Which of the following is path dependent?
U
PdV
P
V
A horizontal platform is rotating with uniform angular velocity around the vertical axis passing through its centre. At some instant of time a viscous fluid of mass 'm' is dropped at the centre and is allowed to spread out and finally fall. The angular velocity during this period
decreases continuously
decreases initially and increases again
remains unaltered
increases continuously
Assertion: Centripetal force does no work.
Reason: Force and displacement are perpendicular to each other.
If both assertion and reason are true and reason is the correct explanation of assertion.
If both assertion and reason are true but reason is not the correct explanation of assertion.
If assertion is true but reason is false.
If assertion is false but reason is true.
A body weighed 250 N on the surface assuming the earth to be a sphere of uniform mass density, how much would it weigh halfway down to the centre of the earth?
195 N
240 N
125 N
210 N
A wire suspended vertically from one of its ends is stretched by attaching a weight of 200 N to the lower end. The weight stretches the wire by 1 mm. Then the elastic energy stored in the wire is
20 J
0.1 J
0.2 J
10 J
A bomb of mass 3.0 kg in air into two pieces of masses 2.0 kg and 1.0 kg. The smaller mass goes at speed of 80 m/s. The total energy imparted to the two fragments is
1.07 kJ
2.14 kJ
2.4 kJ
4.8 kJ
A solid sphere is rolling on a frictionless surface, show in figure with a translational velocity v m/s. If it is to climb the inclined surface then v should be
≥
≥
2gh
10/7 gh
The kinetic energy of a body becomes four times its initial value. The new linear momentum will be
same as the initial value
four times the initial value
twice of the initial value
eight times of the initial value
Maximum energy transfer for an elastic collision will occur if one body is at rest when
m1 = m2
m2 = m1
m1 >> m2
m2 >> m1
