Give the MKS units for each of the following quantities.
(i) Young's modulus
(ii) Magnetic Induction
(iii) Power of a lens
Answer
(A)
i) N/m2, ii) Tesla, iii) Dioptre
2
A rocket moves forward by pushing the surrounding air backwards.
Answer
(B)
FALSE
3
A block of mass 2 kg rests on a rough inclined plane making an angle of $$30^\circ $$ with the horizontal. The coefficient of static friction between the block and the plane is 0.7. The frictional force on the block is
Answer
(A)
9.8 N
4
A ship of mass 3 $$ \times $$ 107 kg initially at rest, is pulled by a force of 5 $$ \times $$ 104 N through a distance of 3 m. Assuming that the resistance due to water is negligible, the speed of the ship is
Answer
(C)
0.1 m/s
5
Two masses of 1gm and 4 gm are moving with equal kinetic energies. The ratio of the magnitude of their linear momentum is
Answer
(C)
$$1:2$$
6
If a machine is lubricated with oil
Answer
(B)
the mechanical efficiency of the machine increases
