Motion class 9 numericals

Here is an article on motion class 9 numericals problems related to motion from class 9 physics:

Mastering Motion: 100 Essential Physics Numericals for Class 9 Students

Understanding motion is a fundamental concept in physics. By solving numerical problems, students can apply their knowledge of motion principles and formulas. This comprehensive guide provides chapter- motion class 9 numericals covering all motion topics in a Class 9 physics curriculum.

Speed, Velocity, and Acceleration numericals

QUESTION): A car travels 300 km in 5 hrs. Find its speed.
ANSWER: 60 km/hr

QUESTION): A train covers a distance of 120 km in 1 hr 20 min. Calculate its speed.
ANSWER: 90 km/hr

QUESTION): A motorcycle increases its speed from 30 km/hr to 60 km/hr in 10 seconds. Determine its acceleration.
ANSWER: 3 m/s2

QUESTION): A cyclist paddles with an acceleration of 0.5 m/s2. If his initial velocity was 2 m/s, what is his final velocity after 15 seconds?
ANSWER: 11.5 m/s

QUESTION): Convert a velocity of 54 km/hr into m/s.
Answer: 15 m/s

Motion Under Gravity numericals

QUESTION): Calculate the final velocity of a ball dropped from the top of a 20m high building. (g=10m/s2)
ANSWER: 20 m/s

QUESTION): Find the time taken by a stone to reach the ground when dropped from a height of 8m. (g=9.8m/s2)
ANSWER: 1.83 s

QUESTION): A ball is thrown vertically upwards with a velocity of 15 m/s. Calculate its height after 5 seconds. (g=-10 m/s2)
ANSWER: 75 m

QUESTION): A stone is projected vertically upwards with a speed of 30 m/s. Determine the time it takes to return to the ground. (g = -9.8 m/s2)
ANSWER: 6.12 s

QUESTION): Calculate the velocity with which a stone needs to be thrown upwards to reach a height of 45m. (g=-9.8m/s2)
ANSWER: 19.6 m/s

Equations of Motion numericals

QUESTION): A car starting from rest attains a velocity of 60 km/hr in 10 seconds. Find its acceleration.
ANSWER: 6 m/s2

QUESTION): A train slows down from 100 km/hr to 50 km/hr in 2 minutes. Calculate its retardation.
Answer: 0.83 m/s2

QUESTION): A bullet fired upwards with a velocity of 150 m/s. If it returns to the ground after 6 s, find the height reached. (g=-10m/s2)
Answer: 1125 m

QUESTION): A car travelling at 72 km/hr applies brakes and stops in 5 seconds. Determine the distance covered during this time.
Answer: 100 m

QUESTION): A ball is thrown upwards with a velocity of 49 m/s. After 3 seconds, calculate its displacement and velocity. (g=-9.8m/s2)
Displacement: 73.5 m, Velocity: -4.4 m/s

Motion Graphs related numericals

QUESTION): The velocity-time graph shows motion of a car. Find its acceleration.

Answer: 2 m/s2

QUESTION): Interpret the given displacement-time graph.

Answer: Object is stationary from 0-5s, moves with uniform velocity between 5-10s, and uniform acceleration from 10-15s.

QUESTION): From the v-t graph, find the distance travelled in first 4 seconds.

Answer: 8 m

QUESTION): A ball is dropped from a height of 10m. Draw its a-t and v-t graph. (g=-10m/s2)

QUESTION): The distance-time graph shows motion of a particle. When is the particle at rest?

Answer: 5-10 seconds

Circular Motion numericals

QUESTION): A car takes a turn of radius 30m at a velocity of 54 km/hr. Calculate its centripetal acceleration.
ANSWER: 3.6 m/s2

QUESTION): A mass of 0.1 kg rotates in a circular path of radius 25cm. If its centripetal acceleration is 1 m/s2, find its speed.
Answer: 0.5 m/s

QUESTION): A ball is whirled in a vertical circle of radius 1.5m with a speed of 12 m/s. Determine the minimum speed at the topmost point.
ANSWER: 9.42 m/s

QUESTION): A vehicle covers a circular track of radius 80m. If its centripetal acceleration is 2 m/s2, calculate its speed.
ANSWER: 16 m/s

QUESTION): A wheel rotating at 1200 rpm has a radius of 10cm. Calculate the centripetal acceleration at a point on its rim.
ANSWER: 7854 m/s2

Newton’s Laws of Motion related numericals

QUESTION): Two forces of 5N and 7N act on a body along the same line. Find the net force and acceleration produced if mass is 2kg.
ANSWER: Net force = 12 N, Acceleration = 6 m/s2

QUESTION): Three forces of 20N, 10N and 30N act on an object of mass 4kg. What is its acceleration?
Answer: 5 m/s2

QUESTION): A cricket ball of mass 150g accelerates at 30 m/s2 when a force of 1.5 N is applied on it. What is the frictional force opposing its motion?
Answer: 0.45 N

QUESTION): A car of 1500 kg exerts a force of 4000 N. Assuming no other force acts, calculate its acceleration.
Answer: 2.67 m/s2

QUESTION): A force of 5 N gives a mass m1 an acceleration of 10 m/s2. If the same force acts on another mass m2, find its acceleration. (m2 = 2m1)
Answer: 5 m/s2

Friction related numericals

QUESTION): The coefficient of static friction between a box and the surface is 0.45. The frictional force is 36 N. Determine the normal reaction.
Answer: 80 N

QUESTION): A force of 250 N is required to just move a 100 kg crate across a floor. What is the coefficient of static friction?
Answer: 0.25

QUESTION): A body of mass 15 kg rests on a horizontal surface. The coefficient of static friction is 0.55. Find the maximum frictional force on the body.
Answer: 82.5 N

QUESTION): The coefficient of kinetic friction between a block and a horizontal surface is 0.3. How much force is required to maintain a velocity of 1.5 m/s? Mass of block is 4 kg.
Answer: 12 N

QUESTION): A horizontal force of 50 N acts on a 10 kg box kept on a rough floor. If the box moves with a velocity of 2 m/s, what is the coefficient of kinetic friction?
Answer: 0.25

Simple Harmonic Motion numericals

QUESTION): A spring has a spring constant of 100 N/m. How much force is required to stretch it by 0.10 m?
Answer: 10 N

QUESTION): A 2 kg mass attached to a spring oscillates with a frequency of 5 Hz. Determine the spring constant. (Use π2=10)
Answer: 100 N/m

QUESTION): The frequency of vibration of a body is 15 Hz. If its time period is 0.5 s, find the amplitude of its motion.
Answer: 0.75 m

QUESTION): A spring has a spring constant of 20 N/m and extends by 5 cm under a load. Calculate the mass required to stretch it.
Answer: 0.25 kg

QUESTION): The frequency of a mass spring system is 10 Hz. If the mass is 4 kg and spring constant is 400 N/m, find the amplitude.
Answer: 0.1 m

Relative Motion numericals

QUESTION): Two cars travel in the same direction at 72 km/hr and 36 km/hr respectively. Find their relative velocity.
Answer: 36 km/hr

QUESTION): A man can swim at a speed of 4 km/hr in still water. If the velocity of the river is 3 km/hr, calculate his relative velocity to the shore.
Answer: 1 km/hr

QUESTION): An aeroplane is flying at 900 km/hr relative to the air. If the air is moving at 100 km/hr towards east, find the velocity of aeroplane relative to ground.
Answer: 1000 km/hr

QUESTION): Wind is blowing from north to south at 10 km/hr. A cyclist rides at 12 km/hr in the westward direction. Find her velocity relative to ground.
Answer: 13 km/hr

QUESTION): A ship moves eastward at 20 km/hr. The water current flows at 5 km/hr to the north. Calculate the resultant velocity of the ship.
Answer: 21 km/hr

Projectile Motion numericals

QUESTION): A ball is thrown horizontally from a height of 20m at a velocity of 15 m/s. How far from the base will it hit the ground? (g=-10m/s2)
Answer: 30 m

QUESTION): A projectile is fired at an angle 60° with initial velocity 20 m/s. What is its maximum height? (g=10m/s2)
Answer: 10 m

QUESTION): A stone is projected at an angle of 30° with a velocity of 20 m/s. Find the time it takes to reach the highest point.
Answer: 3 s

QUESTION): A cricket ball is hit at an angle of 45° with a speed of 50 m/s. Calculate how far away it will land. (g=9.8m/s2)
Answer: 125 m

QUESTION): A particle is projected horizontally from a height of 10m with a velocity of 15 m/s. Determine its time of flight and horizontal range. (g=9.8m/s2)
Answer: Time of flight: 2 s, Range: 30 m

Motion in a Plane numericals

QUESTION): An aircraft flies 200 km east then 100 km north. What is its resultant displacement?
Answer: 223 km, at an angle 66.4° north of east

QUESTION): A ship sails 50 km north, then 45 km northeast. Calculate its net displacement.
Answer: 70.7 km, at an angle 26.6° north of east

QUESTION): An object moves through coordinates (4,2), (6,5) and (1,3). Find its displacement.
Answer: 4.5 units, at an angle 149° counterclockwise from x-axis

QUESTION): An athlete runs 200 m towards north, then 150 m at 30° east of north. Determine his resultant displacement.
Answer: 252 m, at an angle 16° north of east

QUESTION): A particle undergoes three displacements of (3,4), (1,-3) and (-4,2) respectively. What is its net displacement?
Answer: (0,-1)

Uniform Circular Motion numericals

QUESTION): A wheel of radius 2.1 m is moving with a constant speed of 12 m/s. Calculate its angular speed.
Answer: 5.71 rad/s

QUESTION): A merry-go-round rotates 24 times in a minute. If its radius is 4 m, find its linear speed.
Answer: 6.28 m/s

QUESTION): A cycle wheel makes 10000 revolutions in 10 minutes. If its circumference is 2 m, determine the distance travelled.
Answer: 20000 m

QUESTION): A circular path has a circumference of 132 m. What is the angular speed of a particle taking 15 s to complete one revolution?
Answer: 0.5 rad/s

QUESTION): An object completes one rotation every 36 s. Find its angular speed if the radius is 0.6 m.
Answer: 0.17 rad/s

Work, Energy and Power numericals

QUESTION): A force of 5 N displaces a body through 2 m along the direction of force. Calculate the work done.
Answer: 10 J

QUESTION): A man pushes a box through a displacement of 8 m by applying a force of 30 N parallel to displacement. What is the work done?
Answer: 240 J

QUESTION): Find the work done in lifting a grocery bag weighing 20 N through a height of 2 m. (g=10 m/s2)
Answer: 40 J

QUESTION): A 100 N force acts on a 2 kg mass. If its velocity increases from 2 m/s to 8 m/s, determine the work done.
Answer: 200 J

QUESTION): The velocity of a body changes from 4 m/s to 16 m/s when a force of 8 N acts on it. Calculate the work done.
Answer: 96 J

QUESTION): Determine the power when a force of 10 N moves an object along the line of action with a velocity of 5 m/s.
Answer: 50 W

QUESTION): It requires 20 J of work to accelerate a 2 kg mass at 10 m/s2. Calculate the power delivered.
Answer: 200 W

QUESTION): A motor pumps water at the rate of 0.02 m3/s while operating a pump against a head of 30 m. Determine the power if water density is 1000 kg/m3. (g=10 m/s2)
Answer: 6 kW

QUESTION): Find the power needed to lift an object of mass 40 kg vertically upwards at 0.5 m/s. (g=9.8 m/s2)
Answer: 196 W

QUESTION): How much power is needed to accelerate a car of 1500 kg from 30 km/hr to 60 km/hr in 10 seconds?
Answer: 22.5 kW

Conservation of Energy numericals

QUESTION): A ball is dropped from a height of 10 m. With what velocity does it strike the ground? (g=9.8 m/s2)
Answer: 9.9 m/s

QUESTION): A bullet of mass 50 g leaves a gun with a muzzle velocity of 80 m/s. How much kinetic energy does it possess?
Answer: 1600 J

QUESTION): Calculate the potential energy when an object of mass 2 kg is lifted vertically through 5 m. (g=10 m/s2)
Answer: 100 J

QUESTION): A stone of mass 0.5 kg falls from a cliff of height 39.2 m. Determine its kinetic energy just before impact. (g=9.8 m/s2)
Answer: 96.5 J

QUESTION): A pendulum bob of mass 0.1 kg swings from a height of 0.8 m. What is its kinetic energy at the lowest point?
Answer: 0.784 J

Collisions numericals

QUESTION): In an elastic collision of two bodies, one having mass 9 kg and the other 2 kg, final velocities are 4 m/s and 6 m/s respectively. Calculate initial velocities.
Answer: 6 m/s, 2 m/s

QUESTION): A bullet of mass 20 g collides elastically with a stationary wooden block of 0.5 kg. If the bullet rebounds with a velocity of 150 m/s, find the velocity acquired by the block.
Answer: 5 m/s

QUESTION): In a perfectly inelastic collision, two bodies of masses 3 kg and 5 kg collide and move off together. If the initial velocities were 4 m/s and 2 m/s, determine the common final velocity.
Answer: 2.29 m/s

QUESTION): Two balls of masses 100 g and 400 g moving along the same line collide elastically. If the first ball moves at 15 m/s and the second at 45 m/s, determine their velocities after collision.
Answer: First ball: 33.75 m/s, Second ball: 25.5 m/s

QUESTION): Two stones of masses 1 kg and 4 kg moving in opposite directions collide inelastically. If their velocities before collision were 4 m/s and 2 m/s respectively, calculate the common velocity after collision.
Answer: 0.8 m/s

Rotational Motion numericals

QUESTION): A flywheel of mass 10 kg and radius 15 cm is rotating at 300 rpm. Calculate its angular momentum.
Answer: 0.47 kg m2/s

QUESTION): The angular speed of a spinning top is 20 rad/s. What is its angular momentum if its moment of inertia is 0.02 kg m2?
Answer: 0.4 kg m2/s

QUESTION): A disc of moment of inertia 0.48 kg m2 is rotating initially at 10 rad/s. If a constant torque of 8 Nm acts on it, find its angular velocity after 10 s.
Answer: 18 rad/s

QUESTION): A constant torque of 2 Nm produces an angular acceleration of 0.5 rad/s2 in a rigid body. Determine its moment of inertia.
Answer: 4 kg m2

QUESTION): A wheel rotating at 100 rpm comes to rest after 5 s due to a retarding torque. If the moment of inertia of wheel is 0.5 kg m2, calculate the torque.
Answer: 2π Nm

Gravitation numericals

QUESTION): Calculate the value of g at a height 96 km above the earth’s surface. (Radius of earth = 6400 km and g at surface=9.8 m/s2)
Answer: 8.9 m/s2

QUESTION): The mass of earth is 6×1024 kg and radius is 6.4×106 m. Determine the acceleration due to gravity at its centre. (Universal gravitational constant G = 6.67×10-11 Nm2/kg2)
Answer: 0 m/s2

QUESTION): Two objects of masses 100 kg and 500 kg are separated by 5 m. Calculate the gravitational force between them. (G=6.7×10-11 Nm2/kg2)
Answer: 3.34×10-8 N

QUESTION): What is the gravitational potential energy of a satellite of mass 1000 kg orbiting the earth at a height of 2000 km above its surface? (Mass of earth = 6×1024 kg, Radius = 6.4×106 m)
Answer: -5.76×109 J

QUESTION): The radius of earth is 6.4×106 m and mass is 6×1024 kg. Determine the escape velocity from its surface. (G=6.67×10-11 Nm2/kg2)
Answer: 1.12×104 m/s

Fluid Mechanics numericals

QUESTION): Calculate the pressure at a depth of 15 m below the surface of water, given density = 1000 kg/m3 and g = 9.8 m/s2.
Answer: 1

Summary

Solving motion class 9 numericals problems involves applying displacement, speed, velocity, acceleration, Newton’s Second Law and kinematic equations. Mastering these fundamentals builds a strong base in physics kinetics and kinematics for more complex mechanics topics. Consistent practice with motion numericals develops critical problem-solving skills for physics students.