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Force and laws of motion

Why do you fall in the forward
direction when a moving bus
brakes to a stop and fall
backwards when it accelerates
from rest?

10/11/2024

Science

9th

Force and laws of motion

Explain why some of the leaves
may get detached from a tree if
we vigorously shake its branch.

10/11/2024

Science

9th

Force and laws of motion

In the following example, try to
identify the number of times the
velocity of the ball changes:
“A football player kicks a football
to another player of his team who
kicks the football towards the
goal. The goalkeeper of the
opposite team collects the football
and kicks it towards a player of
his own team”. Also identify the agent supplying
the force in each case.

10/11/2024

Science

9th

Force and laws of motion

Which of the following has more
inertia: (a) a rubber ball and a
stone of the same size? (b) a
bicycle and a train? (c) a five-
rupees coin and a one-rupee coin?

10/11/2024

Science

9th

Motion

An artificial satellite is moving in a circular orbit of radius 42250 km. Calculate its speed if it takes 24 hours to revolve around the earth.

10/11/2024

Science

9th

Motion

State which of the following situations are possible and give an example for each of these:
(a) an object with a constant acceleration but with zero velocity
(b) an object moving with an acceleration but with uniform speed.
(c) an object moving in a certain direction with an
acceleration in the perpendicular direction.

10/11/2024

Science

9th

Motion

A ball is gently dropped from a height of 20 m. If its velocity increases uniformly at the rate of 10 m s-2, with what velocity will it strike the ground? After what time will it strike the ground?

10/11/2024

Science

9th

Motion

A driver of a car travelling at 52 km h–1 applies the brakes Shade the area on the graph that represents the distance travelled by the car during the period.
(b) Which part of the graph represents uniform motion of the car?

10/11/2024

Science

9th

Motion

A motorboat starting from rest on a lake accelerates in a straight line at a constant rate of 3.0 m s–2 for 8.0 s. How far does the boat travel during this time?

10/11/2024

Science

9th

Motion

Abdul, while driving to school, computes the average speed for his trip to be 20 km h–1. On his return trip along the same route, there is less traffic and the average speed is 30 km h–1. What is the average speed for Abdul’s trip?

10/11/2024

Science

9th