An inclined plane which makes an angle of 30^o with the horizontal has a velocity ratio of

• A. 2
• B. 1
• C. 0.866
• D. 0.50

Calculate the e.m.f of the cell in the below circuit if its internal resistance is negligible.

• A) 12 V
• B) 8 V
• C) 2 V
• D) 36 V

The physical properties of sound waves can best be described by

• A. reflection and diffraction
• B. polarization and reflection
• C. polarization and diffraction
• D. polarization and refraction

Three forces with magnitudes 16 N, 12 N and 21 N are shown in the diagram below. Determine the magnitude of their resultant force and angle with the x-axis

• A. 7.63N,61°
• B. 8.71N,61°
• C. 7.63N,29°
• D. 8.71N,29°

Correct Answer: B. 8.71N,61°

Explanation

Fx= 12cos32°-16cos26° = -4.20N (right is taken +ve and left is taken -ve)

Fy=12sin32°+16sin26°-21 = -7.63N (up is taken +ve and down is taken -ve)

\(R^2\)= 4.202+7.632

⇒\(R^2\) = 75.86

⇒ R=√75.86

∴R = 8.71 N

tan θ=\(\frac{opp}{adj}\)

⇒tan θ=\(\frac{7.63}{4.20}\)

⇒tan θ =1.8095

⇒ θ = \(tan^-1\) (1.8095)

θ = 61°

∴The angle of the resultant force with the x-axis is 61°

What is the reading of the vernier scale below

• A. 1.88cm
• B. 1.80cm
• C. 1.28cm
• D. 1.97cm

(a) Explain electrolysis

(b) Classify the following substances as electrolytes and non-electrolytes: Sugar solution: paraffin, suit solution and grape fruit juice.

When the downward current flows in a straight vertical conductor, the direction of its magnetic field at a point due north of the wire is?

• A. Upward
• B. North
• C. South
• D. West

When the r.m.s value of a source of electricity supply is given as 240v, it means that the peak value of the supply is

• A. 240v
• B. 340v
• C. 480v
• D. 57600v

What happens when a, certain quantity of pure ice is completely changed to water at 0^oC?

• A. latent heat is absorbed, the mass remains constant, and the volume decreases
• B. latent heat is given out, the mass remains constant and the volume decreases
• C. latent heat is given out, the mass increases and the volume remains constant
• D. latent heat is absorbed, the mass decreases and the volume increases

A metal sheet of area 100cm\(^2\) was heated through 70°C. Calculate its new area if the linear expansivity of the metal is 0.000017K\(^{-1}\).

• A. 100.06 cm²
• B. 100.12cm²
• C. 100.24cm²
• D. 100.36cm²