The rise or fall of a liquid in a narrow tube is because of the

• A. viscosity of the liquid
• B. surface tension of the liquid
• C. friction between the walls of the tube and the liquid
• D. osmotic pressure of the liquid

The thermometric properties of a thermocouple is the change in?

• A) equivalent resistance
• B) electromotive force
• C) colour
• D) pressure

The note produced by a stretched string has a fundamental frequency of 400Hz. If the length of the string is doubled while the tension in the string is increased by a factor of 4, the frequency is

• A. 200Hz
• B. 400Hz
• C. 800Hz
• D. 1600Hz

The density of 400cm³ of palm oil was 0.9gcm^-3 before frying. If the density of the oil was 0.6gcm^-3 after frying, assuming no loss of oil due to spilling, its new volume was?

• A. 1360cm³
• B. 600cm³
• C. 240cm³
• D. 8000m³

A ball is dropped from the top of a tower. Due to air resistance,it reaches terminal velocity. Which of the following statement(s) about its motion is/are correct? i. The acceleration of the ball is zero. ii. The net force on the ball is zero. iii. The velocity of the ball increases.

• A. i only
• B. i and ii only
• C. ii and iii only
• D. i, ii and iii

In the formation of sea breeze. wind blows from

• A. sky to land
• B. sea to sky
• C. land to sea
• D. sea to land

Explain why water in a narrow glass tube has a concave meniscus while mecury in the same tube, has a convex meniscus

The relationship between L and the wavelength I of the stationary wave is

• A. 2L = \(\lambda\)
• B. L = \(\lambda\)
• C. L = \(\frac {\lambda}{3}\)
• D. 4L = 3 \(\lambda\)

(a) Explain diffusion

(b) State one factor that can affect the rate of diffusion.

The main reason for making the cover of a vacuum flask airtight is to prevent heat loss by

• A. convection
• B. conduction
• C. radiation
• D. evaporation