Answer:
A
Explanation:
Iron and gadlinium are both very easily made into magnetic substances. Cobalt is also capable of being magnetized. Aluminum, put in an alloy, can make a magnetic substance, but
Aluminum by itself is not able to be magnetized.
Answer:
option (B)
Explanation:
Young's modulus is defined as the ratio of longitudinal stress to the longitudinal strain.
Its unit is N/m².
The formula for the Young's modulus is given by

where, F is the force applied on a rod, L is the initial length of the rod, ΔL is the change in length of the rod as the force is applied, A is the area of crossection of the rod.
It is the property of material of solid. So, when the 10 wires are co joined together to form a new wire of length 10 L, the material remains same so the young' modulus remains same.
Answer: 
Explanation:
This problem can be solved by the following equation:

Where:
is the change in kinetic energy
is the electric potential difference
is the electric charge
Finding
:


Finally:

Answer:
48.7 J
Explanation:
For a mass-spring system, there is a continuous conversion of energy between elastic potential energy and kinetic energy.
In particular:
- The elastic potential energy is maximum when the system is at its maximum displacement
- The kinetic energy is maximum when the system passes through the equilibrium position
Therefore, the maximum kinetic energy of the system is given by:

where
m is the mass
v is the speed at equilibrium position
In this problem:
m = 3.6 kg
v = 5.2 m/s
Therefore, the maximum kinetic energy is:
