### ВУЗ:

Составители:

Рубрика:

29

2. A weight lifter holds 300 1b over his head. Did he do work on the

weights?

a) Yes, he did, because he pushes his weight up with an equal and …… force.

The distance parallel to the applied force was the …… . So he did work

against …… .

b) The weight lifter didn’t do any work because he didn’t …… his weight

through a horizontal distance.

3. Persons A and B do the same job, but B takes a longer time. Who

expends the greater amount of power?

a) B expends the greater amount of power because he works longer.

b) A ……. the greater amount of power because the same amount of work is

done in each case. Besides, power is the …… of work. To calculate power,

we must …… work by the time required to do it.

4. What is the unit for which we are charged by the electric company?

a) We are paying for energy (……).

b) We are paying for ……, so we are charged for watts.

14. Read the dialogue between Peter and his mother filling in the words

form the list:

consume, multiply, electric, amount, compute, watts, time

M.: I’m worried about the motor you bought yesterday, Peter. I think our a)

………. Bills will be very high as soon as start working on it.

P.: Don’t be afraid, mum. My motor doesn’t b) ……… much energy. It’s a one

horsepower motor.

M.: What does it mean?

P.: One horsepower is 746 W c) ………, or about 0.75 kW. Do you remember

how to d) ……… the amount of energy consumed in a home?

M.: Not exactly.

P.: Energy is power times e) ……… . The cost of electricity is 10 c per kWh.

So, to run the motor for 10 hours will cost only 75 c.

M.: As far as I understand, we first multiply o.75 kW by 10 to compute the f)

……… of energy consumed in 10 hours, which is 7.5 kWh, and then we g)

……… this figure by 10 because he cost of electricity is 10 c per kWh. That’s

pretty cheap.

15. Fill in the missing letters in the following words to five different forms

of energy other than kinetic and potential energy:

H _ _ T, _ _ DIANT, SO _ _ D, C _ E _ I _ AL, NU _ _ EAR.

29 2. A weight lifter holds 300 1b over his head. Did he do work on the weights? a) Yes, he did, because he pushes his weight up with an equal and …… force. The distance parallel to the applied force was the …… . So he did work against …… . b) The weight lifter didn’t do any work because he didn’t …… his weight through a horizontal distance. 3. Persons A and B do the same job, but B takes a longer time. Who expends the greater amount of power? a) B expends the greater amount of power because he works longer. b) A ……. the greater amount of power because the same amount of work is done in each case. Besides, power is the …… of work. To calculate power, we must …… work by the time required to do it. 4. What is the unit for which we are charged by the electric company? a) We are paying for energy (……). b) We are paying for ……, so we are charged for watts. 14. Read the dialogue between Peter and his mother filling in the words form the list: consume, multiply, electric, amount, compute, watts, time M.: I’m worried about the motor you bought yesterday, Peter. I think our a) ………. Bills will be very high as soon as start working on it. P.: Don’t be afraid, mum. My motor doesn’t b) ……… much energy. It’s a one horsepower motor. M.: What does it mean? P.: One horsepower is 746 W c) ………, or about 0.75 kW. Do you remember how to d) ……… the amount of energy consumed in a home? M.: Not exactly. P.: Energy is power times e) ……… . The cost of electricity is 10 c per kWh. So, to run the motor for 10 hours will cost only 75 c. M.: As far as I understand, we first multiply o.75 kW by 10 to compute the f) ……… of energy consumed in 10 hours, which is 7.5 kWh, and then we g) ……… this figure by 10 because he cost of electricity is 10 c per kWh. That’s pretty cheap. 15. Fill in the missing letters in the following words to five different forms of energy other than kinetic and potential energy: H _ _ T, _ _ DIANT, SO _ _ D, C _ E _ I _ AL, NU _ _ EAR.

## Страницы

- « первая
- ‹ предыдущая
- …
- 27
- 28
- 29
- 30
- 31
- …
- следующая ›
- последняя »