physics

A ray of light strikes a plane mirror at an angle of incidence of 35°. If the mirror is rotated through 10°; through what angle is the reflected ray rotated?

A. 70° B. 45° C. 25° D. 20° Correct Answer: Option D = 20° Explanation Whenever a ray of light…

4 years ago

Ice cubes are added to a glass of warm water. The glass and water are cooled by?

A. conduction only B. convection only C. conduction and convection D. convection and radiation Correct Answer: Option C - conduction…

4 years ago

Which of the following consists entirely of vector quantities?

A. Velocity, magnetic flux and reaction B. Tension, magnetic flux and mass C. Displacement, impulse and power D. Work, pressure…

4 years ago

The efficiency of a machine is always less than 100% because the?

A. work output is always greater than the work input B. load lifted is always greater than the effort applied…

4 years ago

On which combination of the above does the weight of an object vary on the earth’s surface?

I. The earth is not spherical but elliptical in shape II. Variation in latitude and longitude III. Rotation of the…

4 years ago

The resultant of two forces acting on an object is maximum if the angle between them is?

A. 45° B. 0° C. 90° D. 180° Correct Answer: Option B = 0° Explanation The resultant of two forces…

4 years ago

A stone of mass 1kg is dropped from a height of 10m above the ground and falls freely under gravity. Its kinetic energy 5m above the ground is then equal to?

A. its kinetic energy on the ground B. twice its initial potential energy C. its initial potential energy D. half…

4 years ago

The colours seen on soap bubbles are due to?

A. Diffraction B. Refraction C. Dispersion D. Interference Correct Answer: Option D - Interference

4 years ago

If the total force acting on a particle is zero; the linear momentum will?

A. Increase B. Decrease C. Be Constant D. Increase then decrease Correct Answer: Option C - Be Constant

4 years ago