The number of beta particles emitted by radioactive substance is twice the number of alpha particles emitted by it. The resulting daughter nuclei is as

1. isobar of parent
2. isomer of parent
3. isotone of parent
4. isotope of parent

Which of the following forces cannot create a moment of force?

1. Action-reaction forces
2. Gravitational forces
3. Electric forces
4. Frictional forces

Assertion Bending of wire does not affect electrical resistance.

Reason Resistance of a wire is proportional to resistivity of material.

1. Both Assertion and Reason are true
2. Both Assertion and Reason are false
3. Assertion is false but Reason is true.
4. Assertion is true but Reason is false

A moving ship continuously sends in ultrasonic pulses down to the sed-bed and records the time delays of the reflected pulses. The variation of time delays recorded versus the positions of the ship is plotted in the following graph. Which of the position indicates the deepest sea bed?

1. A
2. B
3. C
4. D