Physics
Skating on ice is possible because

Ice is cold
The pressure on the ice due to skate melts the ice by lowering its melting point forming a thin film of water
The pressure on the ice due to skate raises its melting point
The surface of ice is smooth

ANSWER DOWNLOAD EXAMIANS APP

Physics
Stationary wave is formed by

Two waves of same frequency travelling in the opposite direction
Two waves of same frequency travelling in the same direction
Two waves of the same speed superposing
A transverse wave superposing a longitudinal wave

ANSWER DOWNLOAD EXAMIANS APP

Physics
X-rays region lies between

Short radio waves and long radio waves
Ultraviolet and visible region
Visible and infra-red region
Gamma-rays and ultraviolet region

ANSWER DOWNLOAD EXAMIANS APP