PHYSICS - MOCK - 01

Q1: A student measured the length of a rod and wrote it as 3.50 cm. Which instrument did he use to measure it?

(a) A screw gauge having 100 divisions in the circular scale and pitch as 1 mm

(b) A screw gauge having 50 divisions in the circular scale and pitch as 1 mm

(c) A meter scale

(d) A vernier calliper where the 10 divisions in vernier scale match with 9 division in the main scale and main scale have 10 divisions in 1 cm

Q2: In an experiment, the angles are required to be measured using an instrument. 29 divisions of the main scale exactly coincide with the 30 divisions of the vernier scale. If the smallest division of the main scale is half-a-degree(= 0.5⁰), then the least count of the instrument is

(a) One degree

(b) Half degree

(c) One minute

(d) Half minute

Q3: A screw gauge gives the following reading when used to measure the diameter of a wire.

Main scale reading : 0 mm

Circular scale reading: 52 divisions

Given that 1 mm on the main scale corresponds to 100 divisions of the circular scale

The diameter of the wire from the above date is

(a) 0.026 cm

(b) 0.005 cm

(c) 0.52 cm

(d) 0.052 cm

Q4: The density of a material in the shape of a cube is determined by measuring three sides of the cube and its mass. If the relative errors in measuring the mass and length are respectively 1.5% and 1%, the maximum error in determining the density is

(a) 3.5 %

(b) 4.5 %

(c) 6 %

(d) 2.5 %

Q5: Resistance of a given wire is obtained by measuring the current flowing in it and the voltage difference applied across it. If the percentage errors in the measurement of the current and the voltage difference are 3% each, then the error in the value of resistance of the wire is

(a) 3%

(b) 6%

(c) zero

(d) 1%

Q6: The density of a solid ball is to be determined in an experiment. The diameter of the ball is measured with a screw gauge, whose pitch is 0.5 mm and there are 50 divisions on the circular scale. The reading on the main scale is 2.5 mm and that on the circular scale is 20 divisions. If the measured mass of the ball has a relative error of 2%, the relative percentage error in the density is

(a) 0.9%

(b) 2.4%

(c) 3.1%

(d) 4.2%

Q7: Which of the following sets have different dimensions?

(a) Pressure, Young’s modulus, stress

(b) Emf, potential difference, electric potential

(c) Heat, work done, energy

(d) Dipole moment, electric flux, electric field

Q8: The least count of the main scale of a screw gauge is 1mm. The minimum number of divisions on its circular scale required to measure 5 μm diameter of a wire is

(a) 50

(b) 200

(c) 100

(d) 500

Q9: A copper wire is stretched to make it 0.5% longer. The percentage change in its electrical resistance if its volume remains unchanged is

(a) 50

(b) 200

(c) 100

(d) 500

Q10: A piece of wood of mass 0.03 kg is dropped from the top of a 100 m height building. At the same time, a bullet of mass 0.02 Kg is fired vertically upward, with a velocity 100 m/s, from the ground. The bullet gets embedded in the wood. Then the maximum height to which the combined system reaches above the top of the building before falling below is (g = 10 m/s)

1. 10 m
2. 30 m
3. 20 m
4. 40 m