Forces and Inclined Planes

According to Newton's first law of motion, an object at rest will remain at rest and an object in motion will continue moving at a constant velocity unless acted upon by an external force. True or False?

• True

• Only for heavy objects

• Sometimes true

• False

Which of Newton's laws of motion states that the acceleration of an object is directly proportional to the net force acting on it and inversely proportional to its mass?

• Newton's second law of motion

• Newton's law of universal gravitation

• Newton's third law of motion

• Newton's first law of motion

When an object is placed on an inclined plane, which force acts parallel to the surface of the plane and opposes the motion of the object?

• normal force

• frictional force

• tension force

• gravitational force

What is the formula to calculate the force of friction on an inclined plane?

• force of friction = coefficient of friction * normal force

• force of friction = coefficient of friction * gravitational force

• force of friction = coefficient of friction * mass

• force of friction = coefficient of friction * weight

A block of mass 5 kg is placed on an inclined plane with an angle of 30 degrees. The coefficient of friction between the block and the plane is 0.2. What is the force of friction acting on the block?

• 10 N

• 8.49 N

• 5 N

• 2.5 N

A 10 kg object is placed on an inclined plane with an angle of 45 degrees. The force of gravity acting on the object is 98 N. What is the component of the force of gravity parallel to the plane?

• 45

• 98

• 69.296

• 10

A block of mass 6 kg is placed on an inclined plane with an angle of 25 degrees. The coefficient of friction between the block and the plane is 0.4. What is the force of friction acting on the block?

• 15.68 N

• 22.32 N

• 10.56 N

• 18.75 N