Work + Efficiency practice

What is the ideal mechanical advantage of an inclined plane which has 4 cm height and 16 cm slope?

• 1/4
• 1
• 16
• 4

What is the efficiency of a machine if 55.3 J of work are done on the machine, but only 14.3 J is produced by the 1machine?

• 0.25 J
• 26%
• 386%
• 3.86 J

Tags

NGSS.HS-PS3-3

What is the efficiency of the machine if the input is 263 J and the output is 142 J? 

• 6.26%
• 54%
• 100%
• 260%

A machine has a work output of 8 joules and requires 10 joules of work input to operate. What is the machine's efficiency?

• 8 J
• 10 J
• 80%
• 800%

Tags

NGSS.HS-PS3-3

What is the mechanical efficiency of a machine whose work input is 250 J and work output is 30 Joules??

• 12 % ME
• 83 % ME 
• .12 % ME 
• .83% ME 

If the weight of the block is 10N, how much force does one have to apply to lift it using this pulley (MA=2)?

• 2N
• 5N
• 10N
• 15N

Tags

NGSS.HS-PS2-1

A box of weight W is lifted by a force F using a lever as shown below.

What is the mechanical advantage of the lever (MA=Input Distance/Output Distance)?

• 0.5

• 2

• 3

• 6

Using a lever, Joe is able to lift a 10,000 N car off of the ground with a force of 1000 N. What is the mechanical advantage of the lever (MA=Output Force/Input Force)?

• 1

• 10

• 100

• 1000

Tags

NGSS.MS-PS2-1

NGSS.MS-PS2-2

if a load of a lever is 100 newtons and the force you apply is 20 newtons, what is your mechanical advantage?

• 120 N
• 5 N
• 2000 N
• 80 N

Mechanical advantage is a measure of how much a machine multiplies the input

• efficiency.
• force.
• power.
• work.

Tags

NGSS.HS-PS2-1