Final review # 1

The graph shows the motion of four cars. Based on the graph, which statement about all the cars is true?

• they are moving at a constant speed

• they are changing their speed during travel

• they are slowing down

• they are stopped

A rock on Earth has a mass 750 kg and a weight of 7,350 N. If the rock is taken into outer space, how will its mass and weight be affected?

• the weight and mass will remain the same because they are not altered by the effects of gravity

• The weight will remain the same, but the mass will change because of the effects of gravity

• The mass will be 76.5kg and the weight will increase because of the effects of gravity

• The mass will be 750 kg but the weight will decrease because of the effects of gravity

As the wheels of a train move along the train tracks, what type of friction exists between the wheels and the tracks

• fluid friction

• rolling friction

• sliding friction

• static friction

A 1,500 kg truck has a net force of 4,200 N acting on it. What is the trucks acceleration?

• 6,300

• 2,700

• 2,8

• ,36

A child fill a bucket with salt water and sand. How are the contents of the bucket classified?

• a solution

• a compound

• a homogeneous mixture

• a heterogeneous mixture

The diagram shows a 40 kg object being pulled in one direction while friction acts on it in the opposite direction. What is the net force on the object

• 160 N

• 140 N

• 120 N

• 20 N

How are the process of melting and freezing similar?

• The are both processes that physically change a substance

• The are both processes that chemically change a substance

• They are both processes where heat is released by a substance

• They are both processes where heat is absorbed by a substance

Which element is classified as a metal?

• Boron (B)

• antimony (Sb)

• phosphorus (P)

• cadmium (Cd)

Four different liquids will be separately poured into a single beaker. The liquids are ethanol, milk oil, and water. The density for each liquid at room temperature is listed in the table. How will the liquids be arranged from bottom to top in the beaker

• milk, water, oil, ethanol

• milk, water, ethanol, oil

• water, milk, oil, ehtanol

• water, oil ethanol, mild

The diagram is the Bohr model of an atom. Which best describes this atom

• It has 6 electrons

• It has a positive charge

• It has 6 valence electrons

• It has a full outermost energy level