- The slope of the straight line displacement-time graph indicates?

**A.**distance traveled**B.**uniform velocity**C.**uniform acceleration**D.**uniform speed

**Correct Option: Answer is A**

- Uniform Velocity = Δs/ Δt

**2. **A man will exert the greatest pressure when he —–?

**A.**lies flat on his back**B.**lies on his belly**C.**stands on both feet**D.**stands on the toes of one foot

**Correct Option: Answer is D**

- Pressure varies inversely as A
- e P ∝1/A

**3. **Which of the units of the following physical quantities are derived?

I. Area

II. Thrust

III. Pressure

IV. Mass

**A.**I, II, III and IV**B.**I, II, and III only**C.**I, II, and IV only**D.**I and IV only

**Correct Option: Answer is B**

**4. **A ball of mass 0.5kg moving at 10ms^{−1}collides with another ball of equal mass at rest. If the two balls move off together after the impact, calculate their common velocity.

**A.**0.2ms^{−1}**B.**0.5ms^{−1}**C.**5.0ms^{−1}**D.**5.5ms^{−1}

**Correct Option: Answer is C**

m_{1} u_{1} + m_{2} u_{2} = (m_{1} + m_{2})v

m_{1}= 0.5kg, u_{1} = 10ms1, m_{2} = 0.5kg, u_{1} = 0

∴(0.5kg x 10) + (0.5 x 0) = (0.5 + 0.5)v

v = 5ms^{1}

**5. **The motion of a body is simple harmonic if the?

**A.**acceleration is always directed towards a fixed point**B.**path of motion is a straight line**C.**acceleration is proportional to the square of the distance from a fixed point**D.**acceleration is constant and directed towards a fixed point

**Correct Option: Answer is A**

**6. **Which of the following is not correct about the molecules of a substance in a gaseous state. They

**A.**are in a constant state of motion**B.**have different speeds**C.**have a temperature which is measured by the average kinetic energy**D.**The collision between the gases is perfectly inelastic

**Correct Option: Answer is D**

Only option D is not correct about the molecules of a substance in a gaseous state, this is because the collisions between gaseous molecules are perfectly elastic.

Gas molecules are constantly in motion and often collide with themselves, bouncing off after each collision. This bouncing off is exactly what we refer to as perfectly elastic.

**7. **A given mass of gas has a pressure of 80 Nm^{−2}at a temperature of 47 C. If the temperature is reduced to 27 C with volume remaining constant, the new pressure is?

**A.**46.0 Nm^{−2}**B.**75.0 Nm^{−2}**C.**80.0 Nm^{−2}**D.**85.3 Nm^{−2}

**Correct Option: Answer is B**

Using P_{1}/T_{1}=P_{2}/T_{2}

P1 = 80Nm^{2}

T1 = 47 + 273 = 320k

T2 = 27 + 273 = 300k

P2?

∴ = P2 = P_{1}T_{2}/T_{1}

= 80×300/320 = 75.Nm^{2}

**8. **0.5kg of water at 10ºC is completely converted to ice at 0ºC by extracting (88000) of heat from it. If the specific heat capacity of water is 42000jkg11Cº. Calculate the specific latent heat of fusion of ice.

**A.**9.0kjkg^{−1}**B.**84.0kjkg^{−1}**C.**134.0kjkg^{−1}**D.**168.0kjkg^{−1}

**Correct Option: Answer is C**

Calculation of specific latent heat of fusion of ice

Heat (H) = 88,000J,

Mass(M)= 0.5kg,

specific heat capacity of water(C) = 4200JkgºC

Specific latent heat of fusion(L) = ?,

Temperature change(Δθ) = θ2 – θ1 = (10 – 0)° = 10°

H = M(CΔθ + L) ->HM = CΔθ + L

L = HM – CΔθ = 88,0000.5 – 4200 × 10

L = 176,000 – 42000 = 134,000

L = 134,000 or 134kj/kg

**9. **Which of the following instruments may be used to measure relative humidity

**A.**Hydrometer**B.**Manometer**C.**Hygrometer**D.**Hypsometer

**Correct Option: Answer is C**

hygrometer, instrument used in meteorological science to measure **the humidity, or amount of water vapour in the air**. Several major types of hygrometers are used to measure humidity.

**10. **A source of sound produces waves in air of wavelength 1.65m. If the speed of sound in air is 330m^{−1}s, the period of vibration in air is?

**A.**200**B.**0.005**C.**0.5**D.**0.02

**Correct Option: Answer is B**

**11. **A boy standing some distance from the foot of a tall cliff claps his hands and hears an echo 0.5s later. If the speed of sound is 340ms^{−1}, how far is he from the cliff?

**A.**680m**B.**170m**C.**34m**D.**85m

**Correct Option: Answer is D**

- V = 2d/t

v = 340ms^{−1}

t = 0.5s

d=2d/2=340×0.52 = 85m

**12. **Which of the following is not a vector quantity?

**A.**momentum**B.**force**C.**temperature**D.**displacement

**Correct Option: Answer is C**

**13. **Calculate the heat energy required to vaporize 50g of water initially at 80ºC if the specific heat capacity of water is 4.23g^{−1}k^{−1}(specific latent heat of vaporization of water is 2260jg^{−1}k^{−1})

**A.**530000J**B.**23200J**C.**17200J**D.**130000J

**Correct Option: Answer is D**

- Solution

- H = mc△θ+ m∫v
- H = ?
- m = 50g, c = 4.23J/gk, ∫v = 2260, △θ= 80ºC
- H = 50 [423 x 80 + 2260]
- = 129920 ≈≈130,000J

**14. **In a series R-L-C circuit at resonance, the voltages across the resistor and the inductors are 30V and 40V respectively. What is the voltage across the capacitator?

**A.**30V**B.**40V**C.**50V

**D. 70V**

**Correct Option: Answer is B**

**15. **If the frequency of an emitted x-ray is 1.6 x 101Hz, the accelerating potential is —– [e = 1.6 x 10-19J, h = 6.63 x 10-34Js]

**A.**6630.0V**B.**663.0V**C.**66.3V**D.**6.6V