Work, Power and Simple Machines Test

As a car drives along, ideally all of the ​ (a)   energy would go toward turning the tires. However as the the tires rub on the road the molecules interact and collide creating ​ (b)   . The friction slows the tires down and converts some of the kinetic energy is converted to ​ (c)   energy causing the tires to ​ (d)  

• Kinetic
• Friction
• Thermal
• Heat up
• Cool down
• Potential

Tags

NGSS.MS-PS3-5

NGSS.MS-PS3-4

NGSS.MS-PS1-4

An electric motor lifts a 20 N block a distance of 6 m. The amount of electrical energy used by the motor is 150 J. How much of the electrical energy has been converted to heat by this process?

• 20 J

• 25 J

• 30 J

• 60 J

Tags

NGSS.MS-PS3-4

NGSS.MS-PS3-3

Solar cell A produces 100 joules of energy, when a light source is shown on it for 3 minutes. Solar cell B produces 200 joules of energy when the same light source is shown on it for 5 minutes. Which solar cell works better?

• Solar cell B, because it produces more energy.

• Solar cell B, because it generates more power.

• Solar Cell A, because it produces energy quicker.

• Solar Cell A, because it generates a greater wattage.

In this energy transfer diagram, the amount of energy lost to the surroundings as heat is

• 250 J

• 450 J

• 700 J

• 950 J

Tags

NGSS.MS-PS3-5

An electric motor lifts a 20 N block a distance of 6 m. The amount of electrical energy used by the motor is 150 J. How much of the electrical energy has been converted to heat by this process?

• 20 J

• 25 J

• 30 J

• 60 J

Tags

NGSS.MS-PS3-5

NGSS.MS-PS3-4

Solar cell A produces 100 joules of energy, when a light source is shown on it for 3 minutes. Solar cell B produces 200 joules of energy when the same light source is shown on it for 5 minutes. Which solar cell works better?

• Solar cell B, because it produces more energy.

• Solar cell B, because it generates more power.

• Solar Cell A, because it produces energy quicker.

• Solar Cell A, because it generates a greater wattage.

Tags

NGSS.MS-ETS1-1

The wind causes this wind turbine to spin, creating electricity. The moving blades are evidence of

• Solar Power

• Work being done

• Potential energy.

• Mechanical advantage.

Tags

NGSS.MS-PS3-5

NGSS.MS-PS3-1

An ordinary light bulb has an efficiency of 5 percent; 100 J of electrical energy is transformed into 5 J of light energy and 95 J of heat energy.

You have just created a new light bulb. If your new light bulb produces 5 J of light at an efficiency of 40 percent, how many joules of electrical energy input does your light bulb require?

Responses

• .083 J

• .125 J

• 8.33 J

• 12.5 J

This is called a Rube Goldberg device. It attempts to perform a simple task through a complex series of steps. Most of the time, what is used for each step?

• Solar Cells

• Simple Machines

• Complex Machines

• Plants and Animals

Tags

NGSS.MS-ETS1-4

All of the ​ (a)   of this machine is useful so it is ​ (b)   efficient.

• force
• weight
• less than 100%
• Work
• 100%

Tags

NGSS.MS-ETS1-1