Answer:
The change in volume is 
Solution:
As per the question:
Coefficient of linear expansion of Copper, 
Initial Temperature, T = 
= 273 K
Final Temperature, T' = 
= 273 + 100 = 373 K
Now,
Initial Volume of the block, V = 
where
V' = Final volume
False the North Star never changes it position
Answer:
When a wire that carries electrical current is placed in a magnetic field the wire experiences a force.
Explanation:
The electric motor is a device which convert electrical energy into mechanical energy ie when current carrying conductor is placed in magnetic field it experience a force. Flemings left hand rule explains the direction of the current.
The electric motor works by attraction and repulsion of magnetic field.
So the option d explains basic concept of simple motor ie when when current carrying wire is placed in the magnetic field it experience magnetic repulsive force.
Answer: C. Metal transfers heat away from the skin by conduction, creating the sensation of coolness.
Explanation: The skin releases heat into the metal bowl since there is a difference in temperature between the two objects. So heat is taken away from the hand abd transfers into the metal bowl by conduction creating a cooler sensation.
