Light, Shadows and Reflection

A scientist designs an anti-glare coating for car windshields. The coating ensures that incoming light does not cause excessive brightness and discomfort for the driver. Which of the following scientific principles is MOST IMPORTANT in designing this coating?

1. Regular reflection
2. Diffused reflection
3. Total Internal reflection
4. Laws of reflection

Answer: (b) Diffused reflection

Pick the odd one out from the following.

1. A burning matchstick
2. A lightning bolt
3. A bioluminescent jellyfish
4. A glow-in-the-dark sticker

Answer: (d) A glow-in-the-dark sticker

An astronaut on the Moon observes Earth completely blocking the Sun. What type of eclipse is this, and what part of the shadow is the astronaut in?

1. Lunar eclipse, umbra
2. Solar eclipse, penumbra
3. Lunar eclipse, penumbra
4. Solar eclipse, umbra

Answer: (a) Lunar eclipse, umbra

A student sees a mirrored word on an ambulance and wonders why it appears reversed. Which of the following concepts explains this phenomenon?

1. Total internal reflection
2. Multiple reflections
3. Diffused reflection
4. Lateral inversion

Answer: (d) Lateral inversion

A light ray strikes a plane mirror at an angle of 35° to the normal. What will be the angle between the incident ray and the reflected ray?

1. 35°
2. 55°
3. 70°
4. 90°

Answer: (c) 70°

Which of the following statements about reflection of light is incorrect? 1.The image formed in a plane mirror is always real. 2. The second law of reflection states that the incident ray, reflected ray, and normal lie in the same plane. 3. Diffused reflection follows the laws of reflection but does not produce a clear image. 4. Regular reflection in plane mirrors can produce vertically inverted images.

1. 1 and 4 only
2. 2 and 3 only
3. 3 and 4 only
4. 1 and 3 only

Answer: (a) 1 and 4 only

A ray of light 'A' enters a mirror maze having all the walls made of mirror as shown in the diagram. It strikes the first mirror at an angle of 45° and ray reflects from it and continues reflecting inside. What will be the direction of the ray 'A' after two reflections?

1. Same direction as the incoming ray (→)
2. Opposite direction (←)
3. Downward (↓)
4. Upward (↑)

Answer: (b) Opposite direction (←)

A team of architects is designing an outdoor stadium where shadow patterns need to be considered for spectator comfort. They notice that shadows under large floodlights appear fuzzy rather than sharp. To minimise this effect and provide clear shade, what should they do?

1. Position the lights closer to the ground
2. Use a single, large, diffused light source
3. Use multiple small light sources instead of one large source
4. Increase the brightness of the lights

Answer: (c) Use multiple small light sources instead of one large source

A scientist is conducting an experiment with a plane mirror. They place a candle 30 cm in front of the mirror and observe its image. The scientist then moves the candle 10 cm closer to the mirror. What will be the new distance of the image from the mirror?

1. 20 cm
2. 30 cm
3. 40 cm
4. 10 cm

Answer: (a) 20 cm

A scientist observes a spaceship in deep space, far from any stars or other light sources. The spaceship is painted completely black with no reflective surfaces. If an astronaut inside the spaceship turns on a flashlight, what will happen?

1. The spaceship will glow faintly as black objects absorb and re-emit light.
2. The light will travel indefinitely, but the spaceship itself will remain invisible.
3. The spaceship will become partially visible as black objects reflect some light.
4. The spaceship will become completely visible because space is never truly dark.

Answer: (b) The light will travel indefinitely, but the spaceship itself will remain invisible.