Nuclei — Physics STD 12 Science — Question

In the phenomenon of interference, write the value of path difference of superimposed waves at the places where constructive and destructive interference occurs.

A scooter weighing 150kg together with its rider moving at 36km/ hr is to take a turn of radius 30m. What horizontal force on the scooter is needed to make the turn possible?

Two proton beams going in the same direction repel each other whereas two wires carrying currents in the same direction attract each other. Explain.

Answer the following questions:
The earth may have even reversed the direction of its field several times during its history of 4 to 5 billion years. How can geologists know about the earth’s field in such distant past?

The calorie ia defined as 1cal = 4.186 joule. Why not as 1cal = 4J to make the conversions easy?

Why does a diamond shine more than a glass piece cut to the same shape?

A string clamped at both ends vibrates in its fundamental mode. Is there any position (except the ends) on the string which can be touched without disturbing the motion? What if the string vibrates in its first overtone?

A long solenoid is fabricated by closely winding a wire of radius 0.5mm over a cylindrical nonmagnetic frame so that the successive turns nearly touch each other. What would be the magnetic field B at the centre of the solenoid if it carries a current of 5A?

In what way is the behaviour of a diamagnetic material different from that of a paramagnetic, when kept in an external magnetic field.