Hey sorry i know there are a lot of questions but please if you can then help me out a bit! thanks ill really appreciate it! and its multiple choice so please choose ONLY ONE. thanks.
1) a nutcracker is a mechanical device that makes work easier by:
a) decreasing the output force
b) increasing the output force
2) a ramp is a mechanical device that makes work easier by:
a) decreasing the input force
b) increasing the input force
3) In which of the following situations does an object have both kinetic and and potential energy?
a) a plane is flying at the height of 3km.
b) a rock is perched at the top of a cliff
4) scissors are an example of which two machines?
a) ramp and first-class lever
b) wedje and first class lever
1) a nutcracker is a mechanical device that makes work easier by:
a) decreasing the output force
b) increasing the output force
2) a ramp is a mechanical device that makes work easier by:
a) decreasing the input force
b) increasing the input force
3) In which of the following situations does an object have both kinetic and and potential energy?
a) a plane is flying at the height of 3km.
b) a rock is perched at the top of a cliff
4) scissors are an example of which two machines?
a) ramp and first-class lever
b) wedje and first class lever
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1) a nutcracker is a mechanical device that makes work easier by:
see nutcracker at website below.
http://nut-crackers.net/wp-content/uploa…
The handles are longer than the jaws, so a small force on the long handles will produce a large force on the short jaws.
The handles are longer than the jaws, so force input is less than force output.
a) decreasing the output force
b) increasing the output force Yes
Work = force * distance
As you push up a ramp, the distance that you move parallel to the ramp is much greater than the distance that the object moves vertically upward.
Vertical distance = Length of ramp * sin angle
Output work = Output force * Length of ramp * sin angle
Input work = Input force * Length of ramp
Length of ramp is greater than Length of ramp * sin angle, so Input force is less than Output work.
2) a ramp is a mechanical device that makes work easier by:
a) decreasing the input force Yes
b) increasing the input force
KE is energy of motion = ½ * mass * velocity^2
PE is energy of position = mass * g * height
3) In which of the following situations does an object have both kinetic and and potential energy?
a) a plane is flying at the height of 3km. Flying is motion and 3km is height YES
b) a rock is perched at the top of a cliff no motion = no KE NO
http://www.professorbeaker.com/simplemac…
see web site above
A pair of scissors:
The two arms that you squeeze together are levers.
The cutting edges of the scissor blades are sharpened to be wedges.
4) scissors are an example of which two machines?
a) ramp and first-class lever
b) wedge and first class lever YES
see nutcracker at website below.
http://nut-crackers.net/wp-content/uploa…
The handles are longer than the jaws, so a small force on the long handles will produce a large force on the short jaws.
The handles are longer than the jaws, so force input is less than force output.
a) decreasing the output force
b) increasing the output force Yes
Work = force * distance
As you push up a ramp, the distance that you move parallel to the ramp is much greater than the distance that the object moves vertically upward.
Vertical distance = Length of ramp * sin angle
Output work = Output force * Length of ramp * sin angle
Input work = Input force * Length of ramp
Length of ramp is greater than Length of ramp * sin angle, so Input force is less than Output work.
2) a ramp is a mechanical device that makes work easier by:
a) decreasing the input force Yes
b) increasing the input force
KE is energy of motion = ½ * mass * velocity^2
PE is energy of position = mass * g * height
3) In which of the following situations does an object have both kinetic and and potential energy?
a) a plane is flying at the height of 3km. Flying is motion and 3km is height YES
b) a rock is perched at the top of a cliff no motion = no KE NO
http://www.professorbeaker.com/simplemac…
see web site above
A pair of scissors:
The two arms that you squeeze together are levers.
The cutting edges of the scissor blades are sharpened to be wedges.
4) scissors are an example of which two machines?
a) ramp and first-class lever
b) wedge and first class lever YES