According to principle of conservation of energy, the total momentum of a system of masses in any direction remains constant unless acted upon by an external force in that direction.

A. true B. False

The friction experienced by a body, when in motion, is known as

The term 'force' may be defined as an agent which produces or tends to produce, destroys or tends to destroy motion.

coefficient of restitution for elastic bodies is one.

The range of projectile on a downward inclined plane is __________ the range on upward inclined plane for the same velocity of projection and angle of projection

Unit of thermal conductivity in M.K.S. units is
(a) kcal/kg m2 °C
(b) kcal-m/hr m2 °C
(c) kcal/hr m2 °C
(d) kcal-m/hr °C
(e) kcal-m/m2 °C.

Thermal conductivity of non-metallic amorphous solids with decrease in temperature
(a) increases
(b) decreases
(c) remains constant
(d) may increase or decrease depending on temperature
(e) unpredictable.

When heat is transferred from one particle of hot body to another by actual motion of the heated
particles, it is referred to as heat transfer by
(a) conduction
(b) convection
(c) radiation
(d) conduction and convection
(e) convection and radiation.

डायमण्ड बैकमोथ" कीट है ?

(A) मटर का

(B) टमाटर का

(C) फूलगोभी का

(D) लौकी का