Unit 2 (Force and Motion) final assessment review

Object A slowed down by 9 cm/s.

Object B sped up by 9 cm/s.

Which object experience the greater change in velocity?

• Object A

• Object B

• they experienced the same change

• Object C

If the same strength force is exerted on 2 objects, the one with ____ mass will experience a greater change in velocity.

• less

• more

Tags

NGSS.MS-PS2-2

During a collision the forces are in the ________ directions.

Tags

NGSS.MS-PS2-1

Three toy boats with the same mass were in a lake. Two boats were moving and one was stopped. Each boat got bumped by another boat, but not in the same direction. All the boats changed speed as a result of being bumped. Use the information in the diagram to answer. Which toy boat(s) experienced the strongest force when it was bumped? How do you know?

• The blue toy boat experienced the strongest force because it takes a stronger force to slow something down than it takes to speed something up.

•  The gray toy boat experienced the strongest force because it had the fastest ending speed.

• The orange and gray toy boats experienced the strongest forces because they both gained the same force as they sped up. The blue boat lost force, so it slowed down

• All three toy boats experienced the same strength force because they changed speed by the same amount.

Answer explanation

It takes the same amount of force to cause an object to speed up by 5 cm/s as it does to slow it down by 5 cm/s because the AMOUNT OF CHANGE was the same (5).

Tags

NGSS.MS-PS2-1

NGSS.MS-PS2-2

Officials are looking into three different ski accidents. The accidents happened when three skiers (all with the same mass) were skiing across flat, snowy ground. They were each bumped by another skier, but not all from the same direction. These skiers changed speed as a result of being bumped. Use the information in the diagram to answer. Which skier(s) experienced the strongest force when bumped? How do you know?

•  The skiers in the yellow and purple sweaters; they both gained the same force as they sped up, but the skier in the red sweater lost force and slowed down.

• The skier in the yellow sweater experienced the strongest force because he has the fastest ending speed.

• All three skiers experienced the same strength force because they changed speed by the same amount.

• The skier in the red sweater because it takes a stronger force to slow something down than to speed it up.

Answer explanation

When thinking about force, we need to pay attention to the AMOUNT of velocity change (not necessarily the type)

Tags

NGSS.MS-PS2-1

NGSS.MS-PS2-2

Curling is a sport in which players push large stones across smooth ice. Three curling stones that have the same mass were sliding across the ice. They were each pushed by a player, but not all from the same direction. Each curling stone changed speed as a result of being hit. Use the information in the diagram to answer. Which curling stone(s) experienced the strongest force when hit? How do you know?

• The blue curling stone experienced the strongest force because it takes a stronger force to slow something down than it takes to speed something up.

• The blue curling stone experienced the strongest force because it changed speed the most.

• The orange curling stone experienced the strongest force because it has the fastest ending speed.

• The yellow and orange curling stones experienced the same strength force because they both gained force, but the blue curling stone lost force.

Answer explanation

Fastest ending speed is NOT the same as greatest change in velocity!!

Tags

NGSS.MS-PS2-1

NGSS.MS-PS2-2

Kristina has three skateboards for her skateboarding competitions. The brown and pink skateboards are of equal mass and more massive than the green skateboard, which has the least mass. One day, she tested the skateboards by giving each a push, but not from the same direction. Use the information in the diagram to answer. Which skateboard(s) experienced the strongest force from Kristina’s push? How do you know?

•  The pink skateboard experienced the strongest force for two reasons: it is a more massive object and it has the fastest ending speed.

• The brown skateboard experienced the strongest force because it requires more force to slow an object down than to speed it up.

• The brown and pink skateboards experienced the strongest force because they are both more massive than the green skateboard and they changed speed by the same amount.

• All three skateboards experienced the same strength force because they changed speed by the same amount.

Answer explanation

to make a more massive object experience the greatest CHANGE in velocity, a stronger force must be exerted!!

Tags

NGSS.MS-PS2-1

NGSS.MS-PS2-2

NGSS.MS-PS3-1

Miniature golf is a game in which players hit a golf ball with a club, which causes the ball to roll along the flat ground. Three golf balls with the same mass were rolling on the ground. Each ball was hit by a golf club, but not from the same direction. All the golf balls changed speed as a result of being hit. Use the information in the diagram to answer. Which golf ball(s) experienced the strongest force when hit? How do you know?

• The white and purple golf balls because they gained force, while the green golf ball lost force.

• The green golf ball because it takes a stronger force to slow something down than to speed something up.

• The green golf ball because it changed speed the most.

•  The white golf ball because it has the fastest ending speed.

Tags

NGSS.MS-PS2-1

NGSS.MS-PS2-2

Three chairs were rolling across a flat office floor. The blue and red chairs are the same mass, and they have more mass than the yellow chair. Each chair was hit by another chair, but not from the same direction. Use the information in the diagram to answer. Which chair(s) experienced the strongest force when hit? How do you know?

• The blue and red chairs experienced the strongest force because they are both more massive than the yellow chair and they changed speed by the same amount.

• The red chair experienced the strongest force because it is as massive as the blue chair and has the highest ending speed.

• All three chairs experienced the same force because they changed speed by the same amount.

• The blue chair experienced the strongest force because it takes more force to slow an object than it takes to make it go faster.

Tags

NGSS.MS-PS2-1

NGSS.MS-PS2-2

NGSS.MS-PS3-1

Hockey is a sport in which players use hockey sticks to push a puck across smooth ice. At practice one day, three different-colored hockey pucks were sliding on the ice. The green hockey puck has less mass than the black and purple hockey pucks, which have the same mass. A player hit each hockey puck with a stick, but not from the same direction. Use the information in the diagram to answer. Which puck(s) experienced the strongest force when hit? How do you know?

• All three hockey pucks experienced the same force because they changed speed by the same amount.

• The black hockey puck; it is more massive and it has the fastest ending speed.

• The purple hockey puck; it takes a stronger force to slow down a more massive object than to speed it up.

•  The black and purple hockey pucks; they have more mass than the green puck, but changed speed by the same amount.

Tags

NGSS.MS-PS2-1

NGSS.MS-PS2-2