Dispersion occurs when white light passes through a glass prism because of the

• A) different hidden colours in the glass
• B) different speeds of the colour in the glass
• C) defects in the glass
• D) high density of the glass

Which of the following statements is not true of the isotopes of an element? They

• A. are atoms of the same element
• B. have the same chemical properties
• C. have the same atomic number
• D. have the same mass number

A short chain is sometimes attached to the back of a petrol tanker to?

• A) generate more friction
• B) ensure the balancing of the tanker
• C) caution the driver when overspeeding
• D) conduct excess charges to the car

An object of mass m moves with a uniform speed v round a circular path of radius r. If its angular speed is ?, the magnitude of the centripetal force acting on it is

• A. \(m \omega^2 r\)
• B. \(\frac{mv^2}{r}\)
• C. \(m \omega r\)
• D. \(\frac{mv^2}{r^2}\)

Which of the following does NOT describe the Image formed by a plane minor?

• A. Erect
• B. Laterally inverted
• C. Same distance from mirror as object
• D. Magnified

If the distance between the object and the pinhole of a pinhole camera is reduced by half the size of the image of the object

• A. Is quadrupled
• B. Is halved
• C. Remains the same
• D. Is double

When a radioactive substance undergoes a beta decay, its

• A. mass number decreases by 1
• B. atomic number decreases by 1
• C. mass number increases by 1
• D. atomic number increases by 1

A tuning fork having a frequency of 312 Hz emits a wave which has a wavelength of 1.10 m. Calculate the velocity of sound

• A. 312.0 ms^-1
• B. 110.0 ms^-1
• C. 343.2 ms^-1
• D. 686.4 ms^-1

If the maximum voltage across a 100ohms resistor is 20V, then the maximum power it can dissipate is

• A. 5.00W
• B. 4.00W
• C. 2.00W
• D. 25W

Which of the following best explains why a person suffers a more severe burn when his skin is exposed to steam than when boiling water pours on his skin?

• A. Steam is at a higher temperature than boiling water
• B. Steam possesses greater heat energy per unit mass than boiling water
• C. Steam spreads more easily over a wider area of the skin man boiling water
• D. Steam penetrates more deeply into the skin than boiling water