Physics - Online Test
Q1. In J.J. Thomson e/m experiment, a beam of electron is replaced by that of muons (particle with same charge as that of electrons but mass 208 times that of electrons). No deflection condition is achieved only if
Answer : Option C
Explaination / Solution:
Q2. Three wires of equal lengths are bent in the form of loops. One of the loops is circle, another is a semi-circle and the third one is a square. They are placed in a uniform magnetic field and same electric current is passed through them. Which of the following loop configuration will experience greater torque ?
Answer : Option A
Explaination / Solution:
Q3. The principle in which a solar cell operates
Answer : Option C
Explaination / Solution:
No Explaination.
Q4. A circular coil with a
cross-sectional area of 4 cm2 has 10 turns. It is placed at the
centre of a long solenoid that has 15 turns/cm and a cross-sectional area of 10
cm2. The axis of the coil coincides with the axis of the solenoid.
What is their mutual inductance?
Answer : Option A
Explaination / Solution:
Q5. The materials used in Robotics are
Answer : Option D
Explaination / Solution:
No Explaination.
Q6. The electric and the magnetic field, associated with an electromagnetic wave, propagating along X axis can be represented by
Answer : Option B
Explaination / Solution:
No Explaination.
Q7. When a biconvex lens of glass having refractive index 1.47 is dipped in a liquid, it acts as a plane sheet of glass. This implies that the liquid must have refractive index,
Answer : Option D
Explaination / Solution:
Since the liquid act as a plane sheet of glass its refractive index is equal to that of glass.
Q8. A ray of light strikes a glass plate at an angle 60º. If the reflected and refracted rays are perpendicular to each other, the refractive index of the glass is,
Answer : Option A
Explaination / Solution:
n = tan ip
= tan (600) = √3
Q9. Two identical conducting
balls having positive charges q1 and q2 are separated by
a center to center distance r. If they are made to touch each other and then
separated to the same distance, the force between them will be
Answer : Option C
Explaination / Solution:
Q10. In photoelectric emission, a radiation whose frequency is 4 times threshold frequency of a certain metal is incident on the metal. Then the maximum possible velocity of the emitted electron will be
Answer : Option B
Explaination / Solution:
From
Enistein's equation
