The equation of a wave travelling along the positive x-direction is given by; y = 0.25 x 10^-3 sin (500t - 0.025x). Determine the angular frequency of the wave motion.

• A. 0.25 x 10^-3rad s^-1
• B. 0.25 x 10^-1rad s^-1
• C. 5.00 x 10²rad s^-1
• D. 2.50 x 10³rad s^-1

If the fraction of the atoms of a radioactive material left after 120 years is 1/64, what is the half-life of the material?

• A. 24 years
• B. 20 years
• C. 10 years
• D. 2 years

An alternating source is connected in series to a capacitor of capacity reactance \( 10^3 \sqrt{3} \) and a resistor of resistance 10³ Ohms. The Impedance of the circuit is...

• A. \( 2000 \sqrt{3} \) Ohms
• B. 2000 Ohms
• C. \( 1000 \sqrt{3} \) Ohms
• D. 1000 Ohms

Steam burn is more severe than that of boiling water because

• A) steam burn is independent of relative humidity
• B) stem possesses greater heat energy per unit mass
• C) water boils at a higher temperature
• D) steam burn is dependent on relative humidity

A string under tension produces a note of frequency 14Hz. Determine the frequency when the tension is quadrupled.

• A. 14Hz
• B. 18Hz
• C. 28Hz
• D. 56Hz

The instrument used for securing a large number of similar charges by induction is called

• A. electrophorus
• B. capacitor
• C. proof-plane
• D. electroscope

When a certain a.c supply is connected to a lamp, it lights with the same brightness as it does with a 12 V d.c battery. Then r.m.s value of the a.c supply is?

• A) 12.0 V
• B) 3.5 V
• C) 17.0 V
• D) 8.5V

An element and its isotope only differ in the number of

• A. protons
• B. electrons
• C. ions
• D. neutrons

Calculate the force acting on an electron of charge 1.5 x 10^-19C placed in an electric field of intensity 105Vm^-1

• A. 1.5x10^-11N
• B. 1.5x10^-12N
• C. 1.5x10^-13N
• D. 1.5x10^-14N

An object weighs 10.0 N in air and 7.0 N in water. What is its weight when immersed in a liquid of relative density 1.5?

• A. 4.50N
• B. 4.67N
• C. 5.50N
• D. 6.67N