3) Look at diagram “Q”. What is the independent variable in this experiment? A. Solution conductivity B. water C. distance D. Acid concentration

The answer is D. The independent variable goes on the X axis.

4) James conducted an experiment to test how weights stretch a rubber band. The chart shows the data James collected during his experiment. What is the most likely assumption James can make from this data? A. If James adds another 25 gram mass the rubber band will stretch to 10cm. B. Rubber bands stretch unevenly. C. Adding another 25 gram mass will cause the rubber band to break. D. All rubber bands stretch the same amount.

The answer is A. If the weght is increased then the length of the rubber band wil increase proportionally.

11) Leon conducted a science fair experiment in which he determined the solubility of Copper Sulfate at different temperatures. What was the dependent variable in his experiment? A. Solubility of Copper Sulfate B. Sulfate C. Mass of the Copper Sulfate D. temperature

The answer is A. The DEPENDENT variable responds to changes in the independent variable. It’s cause and effect. If you change the independent variable, it will, in turn, change the dependent variable. Here Leon changed the temperature, which then caused the solubility to increase.

16. Joe did an experiment. Here is the graph of his data.

Which statement best describes the hypothesis for this experiment? A.Force is equal to acceleration.B.Acceleration is equal to force.C.As force increases acceleration increases.D.As acceleration increases force decreases

The answer is C. Just remember cause and effect. The independent variable causes a change in the dependent variable.

Like this: If the force increases then the acceleration increases.

18. Joe did an experiment. He applied different forces to a toy car and measured the acceleration for each force. Here is his data. What is the dependent variable in Joe’s experiment?

A. AccelerationB.Trial numberC.The forceD.The mass of the objectThe answer is A. If the force increases then the acceleration increases.

19) Look at the chart: What hypothesis is being tested?

A. All wires have exactly the same electrical resistance. B. If the wire length increases then the resistance increases. C. Electrical conductivity varies inversely with wire mass. D. Electrical resistance is inversely proportional to wire length.

The answer is B. The experimenter was changing the wire length ( independent variable) which caused the electrical resistance ( dependent variable) to change.

22) Moe lives in the valley. His twin brother Joe lives at the top of Mile High Mountain. They both have a mass of 75Kg. Which one weighs the most?

A. They both have the same weigh. B. Their sister Loe C. Joe weighs the most. D. Moe weighs the most.

The answer is D. Moe weighs the most because he is closer to the center of mass of the earth.

Cause and effect: If the distance between two masses increases then the gravitational force decreases.

23) Moe has a mass of 75Kg. What is Moe's weight?

A. 750N B. 75N C. 75kg D. 640N

The answer is A. Since weight is a FORCE, just set the problem up:

32. A force of 280N is applied to each cart in order to accelerate each. Arrange the carts in order of increasing acceleration.

The answer is B. Newton’s 2nd Law states that acceleration is inversely proportional to mass. If the mass is greater then the acceleration is less.

33.

The answer is A. Since f=ma, you can solve this problem by calculating the acceleration of each car using a=F/m. Car “A” has the greatest acceleration.

54) Look at the graphs. Which one correctly shows a constant velocity greater than 0m/s?

A. Graph A B. Graph B C. Graph C D. Graph D

The answer is A.

If the time increases, then the distance increases Graph AIf the time increases, then the displacement remains constant. Graph BIf the displacement increases, then the time decreases. Graph CIf the displacement increases then the time decreases. Graph D

Graph C and Graph D are really impossible. Time can’t stand still, and time can’t go backwards!

56) Which equation best explains why increasing a force causes a mass to speed up?

The answer is D.

Newton’s Second law states: Force equals mass times acceleration. If a net force acts upon a mass, then the mass will accelerate in the direction of the force. The acceleration will be proportional to the force, and inversely proportional to the mass… F=ma

57) Suppose a box is sliding along a horizontal frictionless surface. According to Newton’s first law the box will:

A. eventually stop because of kinetic friction if the net force is zero. B. continue moving at a constant velocity because net force is zero. C. accelerate gradually if the net force is zero. D. slow down because the net force is zero.The answer is B.

Newton’s First Law states that an object can have a constant velocity with NO force acting on it.

Newton’s First Law - An object in motion will continue in motion, and an object at rest will remain at rest, if the net force acting on the object is zero.

58) Which of the objects is undergoing a positive acceleration?

A. A car slowing from 20km/h to a stop in 10.0s. B. A car sitting still in the driveway. C. A car traveling at a constant speed of 20km/h while going around a curve. D. A car traveling at a constant speed of 100km/h on a straight road.

The answer is C.

Even though the speed is constant as the car goes around the curve, the car IS accelerating. An object is accelerating if it speeds up, slows down, or CHANGES DIRECTION.

59) What is the acceleration of a car that speeds up from 20km/h to 30km/h in 5.0s?

A. 2 B. 2m/s C. 2m/s2

D. 2km/h/s

The answer is D

61) If a toy car accelerates at .5m/s2 when a 2N force is applied to it. What is the mass of the toy car?

A. 4kg B. 4N C. 1kg D. 4m/s

The answer is A.

You must use the force equation to solve for mass…

62) On the Earth Joe the astronaut has a mass of 75kg and a weight of 735Newtons. Which statement best describes what his weight and mass would be on the Moon?

A. His weight would be less on the Moon. His mass would be the same. B. His weight would be less and his mass would decrease. C. He would have the same mass and the same weight. D. His weight would stay the same and his mass would increase.

The answer is A.

The Moon has less mass than the Earth so it has about 1/6th the acceleration due to gravity. This is why you would weigh only 1/6th as much on the Moon. Go to the Moon and your mass remains the same.

63) Where would a person have the greatest weight?

A. On the top of a mountain. B. At the bottom of a valley. C. On the Moon D. Weight is always the same no matter where one is.

The answer is B.

The closer you are to the center of mass of the Earth, the greater the gravitational attraction, and therefore, the greater your weight.

Cause and effect…If you decrease the distance between two masses then the gravitational attraction will increase.

68) When making a line graph:

A.It makes no difference which variable goes where.B. The independent variable goes on the "y" axis.C. The dependent variable goes on the "x" axis.D. The independent variable goes on the "x" axis.

D. The independent variable goes on the "x" axis.

75) A sample of an unknown liquid was found to have a volume of 30cm3 and a mass of 25g. What is the density of the substance?

A. .47g/ml B. .8g/ml C. density cannot be determined with this information. D. 1.5g/ml

B. .8g/ml

87. F= m x a mathematically represents which of the following. A. Newton’s First Law B. Newton’s Second Law C. Newton’s Third law D. Pascal’s Principle

B. Newton’s Second Law

94) Two objects, A and B, are both acted on by a 2.0N force. B accelerates at 3.0m/s/s and A accelerates at 1.5m/s/s. Which of the following statements is true?

A.Object A has the greatest mass because it has the least acceleration.

B. Both objects must have the same mass.C. More information is needed to determine which object

has the greatest mass.D. Object B has the greatest mass because it has the

greatest acceleration.

A. Object A has the greatest mass because it has the least acceleration.

101) List the general steps of a scientific method.

A. Problem, observation, hypothesis, experiment, analysis, conclusionB. Observation, Hypothesis, problem, analysis, conclusionC. theory, hypothesis, experiment, conclusion, lawD. observation, analysis, conclusion, problem, experiment, hypothesis

A. Problem, observation, hypothesis, experiment, analysis, conclusion

107) Joe's car has a mass of 2000kg. What is the weight of Joe's car?

A. 20 000N B. 2000kg C. 1000N D. 19 600kg

A. 20 000N

108) If Joe's car accelerates at 3.0m/s/s, what will the velocity of his car be after 4.0s?

A. 12.0N B. 10m/s C. 8m/s D. 12m/s

D. 12m/s

109) If it takes 2.0s for Joe to slow his car from 30km/h to 20km/h what is his acceleration?

A. +2m/s/s B. -5m/s/s C. 4m/s D. -5km/h/s

D. -5km/h/s