One end of a steel girder in a bridge is not fixed, but is kept on rollers. Give the reason.

Ethane is used as fuel. Give one reason.

Methane is used as fuel. Give one reason.

Why are iron bridges mounted on steel rollers? Explain.

One end of a metal rod is kept in a furnace. In steady state, the temperature of the rod

One end of a metal rod is kept in a furnace. In steady state, the temperature of the rod

In specific resistance measurement of a wire using a meter bridge, the key k in the main circuit is kept open when we are not taking readings. The reason is

Dissociation of oxyhaemoglobin is more in an active tissue than in a less active one. Give one reason for this.

One end of a spring is kept fixed while the other end is stretched by a force as shown in the diagram. Name one instrument which works on the above principle.

One end of a spring is kept fixed while the other end is stretched by a force as shown in the diagram. Copy the diagram and mark on it the direction of the restoring force.

A one meter long glas tube is open at both ends. One end of the tube is dipped into a mercury cup, the tube is kept vertical and the air is pumped out of the tube by connecting the upper end ot a suction pump. Can mercury be puled up into the pump by this process?