science
Grade-7
Easy
Question
What forces are acting on a ball when it is thrown up until it reaches the topmost point? How are they aligned?
- Gravitational and normal forces, opposite to each other
- Gravitational and applied forces, opposite to each other
- Gravitational and applied forces, in the same direction
- Gravitational and normal forces, in the same direction
Hint:
Ball starts motion due to applied force and slows down due to gravitational force.
The correct answer is: Gravitational and applied forces, opposite to each other
- When a ball is thrown vertically upward applying a force, it starts its vertical motion with initial velocity(there is no normal force).
- As it moves upwards vertically its velocity reduces gradually under the influence of gravitational force working towards the opposite direction of the ball's motion.
- Accelerating the ball downwards (slowing it down).
- Hence, the forces acting are gravitational and applied in opposite direction.
- So, the correct option is b.
Related Questions to study
science
When a skydiver deploys her parachute, she is under the action of ____.
When a skydiver deploys her parachute, she is under the action of ____.
scienceGrade-7
science
A truck is moving forward on the road and experiencing a frictional force of 203 N. The force applied by its engine is 743 N. Considering the air resistance to be negligible, calculate the force that the break needs to apply on it in order to stop it. In which direction should this force be applied?
A truck is moving forward on the road and experiencing a frictional force of 203 N. The force applied by its engine is 743 N. Considering the air resistance to be negligible, calculate the force that the break needs to apply on it in order to stop it. In which direction should this force be applied?
scienceGrade-7
science
A skydiver jumps from a high-flying helicopter. Which of the statements about him is true?
A skydiver jumps from a high-flying helicopter. Which of the statements about him is true?
scienceGrade-7
science
A car accelerating uniformly on the road comes across a rough road so that the frictional force increases sufficiently to balance out the forward force exerted by the engine. What would happen to the motion of the car?
A car accelerating uniformly on the road comes across a rough road so that the frictional force increases sufficiently to balance out the forward force exerted by the engine. What would happen to the motion of the car?
scienceGrade-7
science
A book lying on a table was pushed, and it moved. What kinds of forces were acting on the book when it was lying on the table and when it moved?
- Gravitational force is a non-contact force.
- Friction is a contact force.
- Reaction force due to table is a contact force.
- Contact force can be a push, full or friction.
A book lying on a table was pushed, and it moved. What kinds of forces were acting on the book when it was lying on the table and when it moved?
scienceGrade-7
- Gravitational force is a non-contact force.
- Friction is a contact force.
- Reaction force due to table is a contact force.
- Contact force can be a push, full or friction.
science
An avocado hangs from a branch of a tree. What kinds of forces are acting on it?
An avocado hangs from a branch of a tree. What kinds of forces are acting on it?
scienceGrade-7
science
An object is under the action of two forces that balance out each other. The forces are ____.
An object is under the action of two forces that balance out each other. The forces are ____.
scienceGrade-7
science
Vimal had a remote-control toy car, which had separate buttons to control its velocity and direction of motion. He wanted it to be under balanced forces. How should he use the remote for that?
A) He should not start the car or use the remote.
B) He should start the car and then keep on increasing its velocity uniformly
C) He should start the car and make it move in a circular path
D) He should start the car and fix its velocity at a certain value and fix its direction of motion.
- Centripetal acceleration is needed for circular motion. Means there will be net centripetal force also.
- Velocity is increasing means there is acceleration. And hence, there is net force.
Vimal had a remote-control toy car, which had separate buttons to control its velocity and direction of motion. He wanted it to be under balanced forces. How should he use the remote for that?
A) He should not start the car or use the remote.
B) He should start the car and then keep on increasing its velocity uniformly
C) He should start the car and make it move in a circular path
D) He should start the car and fix its velocity at a certain value and fix its direction of motion.
scienceGrade-7
- Centripetal acceleration is needed for circular motion. Means there will be net centripetal force also.
- Velocity is increasing means there is acceleration. And hence, there is net force.
science
A biker is moving on a circular track. What kind of forces are acting on him?
A biker is moving on a circular track. What kind of forces are acting on him?
scienceGrade-7
science
Pick the odd one out.
Pick the odd one out.
scienceGrade-7
science
Calculate the gravitational force acting on the ball in the figure below
Calculate the gravitational force acting on the ball in the figure below
scienceGrade-7
science
The greater the net force opposite to the direction of motion, the ___ the ____ in the direction of motion.
The greater the net force opposite to the direction of motion, the ___ the ____ in the direction of motion.
scienceGrade-7
science
Find the net force on the car. The various forces associated with the car are given below.
Find the net force on the car. The various forces associated with the car are given below.
scienceGrade-7
science
The acceleration of a moving body increases. What could be the reason behind it?
A) Increase in the unbalanced forces
B) Decrease in the unbalanced forces
C) Increase in the balanced forces
D) Increase in the net force
E) Decrease in the net force
The acceleration of a moving body increases. What could be the reason behind it?
A) Increase in the unbalanced forces
B) Decrease in the unbalanced forces
C) Increase in the balanced forces
D) Increase in the net force
E) Decrease in the net force
scienceGrade-7
science
A car is moving on a road. What are the forces acting opposite to its direction of motion?
A) Frictional force
B) Force exerted by the engines
C) Air resistance
D) Force exerted by the brakes
A car is moving on a road. What are the forces acting opposite to its direction of motion?
A) Frictional force
B) Force exerted by the engines
C) Air resistance
D) Force exerted by the brakes
scienceGrade-7
