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A bus starting from rest moves with a uniform acceleration of 0.1 ms^-2 for 2 minutes. Find (a) the speed acquired, (b) the distance travelled.

Given The bus starting from rest moves with a uniform acceleration of 0.1 m s-2 for 2 minutes Find out Acceleration and distance travelled... View Article

What is the quantity which is measured by the area occupied below the velocity-time graph?

The area occupied under the velocity-time graph is the distance travelled by the moving body. The area under a velocity-time graph is the... View Article

What can you say about the motion of an object if its speed-time graph is a straight line parallel to the time axis?

When the slope of a speed-time graph is a straight line parallel to the time axis, the object is moving with uniform speed. Since there is... View Article

What can you say about the motion of an object whose distance-time graph is a straight line parallel to the time axis?

When the slope of the distance-time graph is a straight line parallel to the time axis, the object is at the same position as time passes. That... View Article

When will you say a body is in (i) uniform acceleration? (ii) non-uniform acceleration?

Answer: Acceleration is defined as the rate of change of velocity with respect to time. Acceleration is a vector quantity as it has both... View Article

During an experiment, a signal from a spaceship reached the ground station in five minutes. What was the distance of the spaceship from the ground station? The signal travels at the speed of light, that is, 3 × 10⁸m/s.

Given that The signal travels in a straight line, the distance between the spaceship and the ground station is equal to the total distance... View Article

What does the path of an object look like when it is in uniform motion?

The path of an object in uniform motion is a straight line. Uniform Motion:This type of motion is defined as the motion of an object in which the... View Article

Distinguish between speed and velocity.

The velocity of an object can be defined as the rate of change of the object’s position with respect to a frame of reference and time. It might... View Article

A farmer moves along the boundary of a square field of side 10m in 40 s. What will be the magnitude of displacement of the farmer at the end of 2 minutes 20 seconds from his initial position?

Given that The farmer covers the entire boundary of the square field in 40 seconds Find out The magnitude of displacement of the farmer at... View Article

Find the focal length of a lens of power -2.0 D. What type of lens is this?

The power of the lens is known as the inverse of the focal length of the lens measured in meter(m). Power of lense = 1/ focal length in meter.... View Article

An object 5 cm is placed at a distance of 20 cm in front of a convex mirror of radius of curvature 30 cm. Find the position, nature and size of the image.

Object distance (u) = – 20 cm Object height (h) = 5 cm Radius of curvature (R) = 30 cm Radius of curvature = 2 × Focal length R = 2f... View Article

Name the type of mirror used in the following situations. (a) Headlights of a car (b) Side/rear-view mirror of a vehicle (c) Solar furnace Support your answer with reason.

Answer: A mirror is defined as a reflecting surface and can be explained by the law of reflection, which states that when a ray of light is made... View Article

Why does the sky appear dark instead of blue to an astronaut?

The sky appears dark instead of blue to an astronaut, as a scattering of light does not take place outside the earth’s atmosphere. There is no... View Article

A person needs a lens of power -5.5 dioptres for correcting his distant vision. For correcting his near vision he needs a lens of power +1.5 dioptre. What is the focal length of the lens required for correcting (i) distant vision, and (ii) near vision?

The ability of the lens of the eye to adjust its focal length to clearly focus rays coming from distant as well from near objects on the retina... View Article

The least distance of distinct vision for a young adult with normal vision is about (a) 25 m (b) 2.5 cm (c) 25 cm (d) 2.5 m

(c) 25 cm 25 cm is the least distance of distinct vision for a young adult with normal vision. The range of vision of a normal human eye is... View Article

The human eye forms an image of an object at its (a) cornea (b) iris (c) pupil (d) retina

(d) retina The retina is the layer of nerve cells lining the back wall inside the eye. This layer senses light and sends signals to the brain... View Article

he human eye can focus objects at different distances by adjusting the focal length of the eye lens. This is due to (a) presbyopia (b) accommodation (c) near-sightedness (d) far-sightedness

(a) Presbyopia A difficulty to see both nearby and far objects is called Presbyopia. Presbyopia is caused as part of the natural ageing... View Article

A student has difficulty reading the blackboard while sitting in the last row. What could be the defect the child is suffering from? How can it be corrected?

The student is suffering from short-sightedness or myopia. Myopia can be corrected by the use of a concave or diverging lens of appropriate... View Article

What is the far point and near point of the human eye with normal vision?

Near Point The minimum distance of the object from the eye, which can be seen distinctly without strain is called the near point of the eye.... View Article

A person with a myopic eye cannot see objects beyond 1.2 m distinctly. What should be the type of corrective lens used to restore proper vision?

An individual with a myopic eye should use a concave lens of focal length 1.2 m so that he or she can restore proper vision. Myopia or... View Article

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