PHY101 Midterm Updated Solved MCQs by Mickey Ch

Q1. The lowest tone produced by a certain organ comes from a 3.0-m pipe with both ends open. If the speed of sound is 340m/s, the frequency of this tone is approximately___

1. 7Hz
2. 14 Hz
3. 28 Hz
4. 57 Hz

Correct answer: 57 Hz

Q2. The SI standard of time is based on is.

1. the daily rotation of the earth
2. the frequency of light emitted by Kr86
3. the yearly revolution of the earth about the sun
4. none of these

Correct answer: none of these

Q3. A net torque applied to a rigid object always tends to produce:

1. rotational equilibrium
2. linear acceleration
3. angular acceleration
4. rotational inertia

Correct answer: rotational equilibrium

Q4. A nanosecond is_____

1. 109 s
2. 10−9 s
3. 10−10 s
4. 10−10 s

Correct answer: 10−9 s

Q5. To raise the pitch of a certain piano string, the piano tuner:

1. loosens the string
2. tightens the string
3. shortens the string
4. lengthens the string

Correct answer: shortens the string

Q6. An object attached to one end of a spring makes 20 vibrations in 10 s. Its angular frequency is:

1. 12.6 rad/s
2. 1.57 rad/s
3. 2.0 rad/s
4. 6.3 rad/s

Correct answer: 2.0 rad/s

7. A force of 5000N is applied outwardly to each end of a 5.0-m long rod with a radius of

Q34. 0 cm and a Young's modulus of 125 × 108 N/m2. The elongation of the rod is:

1. 0.0020mm
2. 0.0040mm
3. 0.14mm
4. 0.55mm

Correct answer: 0.55mm

Q8. In 1866, the U. S. Congress defined the U. S. yard as exactly 3600/3937 international meter. This was done primarily because:

1. length can be measured more accurately in meters than in yards
2. the meter is more stable than the yard
3. this definition relates the common U. S. length units to a more widely used system
4. the members of this Congress were exceptionally intelligent

Correct answer: this definition relates the common U. S. length units to a more widely used system

Q9. There is no SI base unit for area because:

1. an area has no thickness; hence no physical standard can be built
2. we live in a three (not a two) dimensional world
3. it is impossible to express square feet in terms of meters
4. area can be expressed in terms of square meters

Correct answer: area can be expressed in terms of square meters

Q10. A particle oscillating in simple harmonic motion is:

1. never in equilibrium because it is in motion
2. never in equilibrium because there is always a force
3. in equilibrium at the ends of its path because its velocity is zero there
4. in equilibrium at the center of its path because the acceleration is zero there

Correct answer: never in equilibrium because it is in motion

Q11. In simple harmonic motion, the restoring force must be proportional to the:

1. amplitude
2. frequency
3. velocity
4. displacement

Correct answer: displacement

Q12. Which of the following weighs about a pound?

1. 0.05 kg
2. 0.5kg
3. 5 kg
4. 50 kg

Correct answer: 50 kg

Q13. The number of significant figures in 0.00150 is:

1. 2
2. 3
3. 4
4. 5

Correct answer: 3

Q14. A 160-N child sits on a light swing and is pulled back and held with a horizontal force of 100 N. The magnitude of the tension force of each of the two supporting ropes is:

1. 60N
2. 94N
3. 120N
4. 190N

Correct answer: 120N

Q15. Mercury is a convenient liquid to use in a barometer because:

1. it is a metal
2. it has a high boiling point
3. it expands little with temperature
4. it has a high density

Correct answer: it has a high density

Q16. 1 mi is equivalent to 1609 m so 55 mph is:

1. 15 m/s
2. 25 m/s
3. 66 m/s
4. 88 m/s

Correct answer: 25 m/s

Q17. A sphere with a radius of 1.7 cm has a surface area of:

1. 2.1 × 10−5 m2
2. 9.1 × 10−4 m2
3. 3.6 × 10−3 m2
4. 0.11 m2

Correct answer: 3.6 × 10−3 m2

Q18. A right circular cylinder with a radius of 2.3 cm and a height of 1.4 cm has a total surface area of:

1. 1.7 × 10−3 m2
2. 3.2 × 10−3 m2
3. 2.0 × 10−3 m3
4. 5.3 × 10−3 m2

Correct answer: 5.3 × 10−3 m2

Q19. 1 m is equivalent to 3.281 ft. A cube with an edge of 1.5 ft has a volume of:

1. 1.2 × 102 m3
2. 9.6 × 10−2 m3
3. 9.6 × 10−2 m3
4. 10.5m3
5. 9.5 × 10−2 m3

Correct answer: 9.6 × 10−2 m3

Q20. For an object in equilibrium the net torque acting on it vanishes only if each torque is calculated about:

1. the center of mass
2. the center of gravity