Valerie 發問於 社會及文化語言 · 6 年前

# English~~~urgent(20pt)

Human beings are not born with special abilities but there is a belief that we are the most intelligent creatures in the world. We create different devices to make work easier by reducing the amount of force involved. For example, _________are used to slide heavy objects up.

Q1)Fill in the blank with the two words below:

1)Pulleys

2)Ramps

Q2)Can objects "slide up"?

### 3 個解答

• 6 年前
最愛解答

(Q1)ramps

(Q2)Objects can slide up and slide over a slippery surface by a ramp (or slope) which is a gadget,an instrument, for reducing the amount of force involved as a machine does in Physics.Other answers are possible,please.

2015-03-31 07:37:08 補充：

Amendment:-We apply "a pulling force" to the object......Objects can-----

• 6 年前

Q1

The answer should be 2) Ramps

Q2

We can use ramp to slide a heavy object up over a slippery surface when we apply a pulling force to the object.

Credit should be given to 意見者：Duncan

A picture is worth a thousand words.

slide (intransitive verb) = move along a smooth surface

An object slides down over a slippery surface. (~ i.e. under gravity)

slide (transitive verb) = cause (a person or thing) to move across or down a surface while maintaining contact with it

An object is slid up the slippery surface of a ramp by a pulling force.

In physics, work done = force X distance

We use less force, but the object is moved over a longer distance.

A heavy load may be raised by pulling it along a sloping surface than by lifting it vertically.

2015-03-31 02:19:10 補充：

To TOMING88

Watch your language! ~ I mean the way you word it.

You always come up with half-baked ideas.

How can an object slide up over a slippery surface by a ramp (on its own)?

地心引力顛倒?

You should mention the pulling force applied to the object.

資料來源： Oxford English Dictionary