Calculate the position of an object placed in front of a convex mirror having focal length of 12 cm such that an image is formed 6 cm away from the mirror

• A) 4. 0 cm
• B) 3. 0 cm
• C) 12.0 cm
• D) 9.0 cm

The term torque means

• A. the moment
• B. the resultant of several forces acting on a body in equilibrium
• C. two equal and oposite forces whose lines of action do not coincide
• D. two coplaner forces at right angles to each other

A boat travels due east at a speed 40ms^-1s across a river flow due south at 30ms^-1s. What is the resultant speed of the boat?

• A. 1.3ms^-1
• B. 10.0ms^-1
• C. 50.0ms^-1
• D. 70.0ms^-1

A generator is on daily use and in the process, ten 60 W and five 40 W tungsten bulbs are on for the same time interval. the energy consumed daily is?

• A) 0.96 kWh
• B) 19.2 kWh
• C) 9.60 kWh
• D) 19.20 kWh

If the temperature of water is gradually increased from 0° to 4°C, the density of the water within this range

• A. increases for a while and then decreases
• B. decreases for a while and then increases
• C. increases gradually
• D. decreases gradually

The material used for constructing the core of an electromagnet is

• A. iron
• B. carbon
• C. copper
• D. steel

Which of the following statements on the use of X-rays is incorrect? X-rays are used

• A. In a hospital to obtain photographs of tissues and bones in the body
• B. For the treatment of malignant growths like cancer cells
• C. In detecting fingerprints
• D. To reveal hidden flaws in metal castings and welded joints work of art

A battery of e.m.f 10V an internal resistance 2? is connected to a resistance of 6Ω. Calculate the p.d

• A. 8.75V
• B. 7.50V
• C. 5V
• D. 2.50V

A simple pendulum makes 50 oscillations in one minute. What is its period of oscillation?

• A. 0.02s
• B. 0.20s
• C. 0.83s
• D. 1.20s

In the diagram below, if the south poles of two magnets stroke a steel bar, the polarities at X and Y will respectively be

• A. south and north
• B. north and south
• C. north and north
• D. south and south