A skydiver jumped out of an airplane. On reaching a terminal speed of 60 ms⁻¹, she opened her parachute. Which of the following describes her motion after opening her parachute?

• She went upwards for a short time, before falling to Earth at a speed of 60 ms⁻¹.

• She continued downwards at 60 ms⁻¹, but hit the ground with less force.

• She continued to fall but reached a new terminal speed of less than 60 ms⁻¹.

• She went upwards for a short time, before falling to Earth at a speed of less than 60 ms⁻¹

Tags

NGSS.HS-PS2-1

The graph is a speed versus time graph for an object that is moving in a straight line.

The distance travelled by the object during the first 4.0 seconds is

• 80m

• 40m

• 20m

• 5m

The diagram shows a person attempting (but failing) to lift a heavy suitcase of weight W. The magnitude of the vertical upwards pull of the girl on the suitcase is P and the magnitude of the vertical reaction of the floor on the suitcase is R.

Which equation correctly relates W, P and R?

• W=P+R

• W>P+R

• W<P+R

• W=P=R

Tags

NGSS.HS-PS2-1

Objects A and B collide together. They end up joined together and stationary. During the collision, a force +F is exerted on object A by object B. According to Newton’s third law, there will also be a force of

• −F acting on object B.

• −F acting on object A.

• +F acting on object B.

• +F acting on object A.

A student is sitting on a chair. One force that is acting on the student is the pull of gravity. According to Newton’s third law, there must be another force which is

• the upward push of the chair on the student.

• the downward force on the student.

• the downward push of the chair on Earth.

• the upward force on Earth.

An object moves in the x-y plane. The graphs below show how the component of its velocity V_x in the x-direction and the component of its velocity V_y in the y-direction, vary with time t

• The particle is moving in a parabola.

• The particle is moving with simple harmonic motion.

• The particle is moving with constant velocity in a straight line.

• The particle is moving in a circle.

Two balls of different mass are dropped from the top of a tall building one after the other. The distance between the balls

• increases with time.

• depends on the initial velocity only.

• remains constant.

• depends on the mass of the balls.

Tags

NGSS.HS-PS2-1

NGSS.HS-PS2-4

The graph shows how the velocity of a particle varies with time.

Which of the following graphs correctly shows how the acceleration of the particle varies with time?

• 
• 
• 
• 

Tags

NGSS.HS-PS2-1

Two cars, X and Y, are travelling towards a junction. The velocity of car X is V_X and car Y is V_Y.

Which of the following vectors represent the velocity of Y relative to X?

• 
• 
• 
• 

If a moving object is subject to a constant force, which of the following can be correctly deduced from Newton’s first law?

• The object continues to move with a changing velocity.

• The object continues to move with a constant velocity.

• The object continues to move with a changing direction.

• The object continues to move in the same direction.