mọi người giải chi tiết câu c và d giúp em với ạ. Câu a và b chỉ cần kết quả cuối thôi, không cần giải ra đâu ạ.
Một vật 2kg được ném thẳng lên cao với vận tốc đầu 8m/s, tại vị trí cách mặt đất 10m. Lấy g=10m/s. Bỏ qua ma sát với không khí
a. Xác định cơ năng
b. Độ cao cực đại mà vật nhận được là bao nhiêu
c. Tính độ cao mà tại đó thế năng bằng 3 lần động năng
d. Tính thời gian từ lúc ném đến khi vật chạm đất
Một lò xo có k = 100N/m, đặt nằm ngang 1 vật có m=0.2 kg gắn vào đầu lò xo, đầu còn lại cố định. Kéo vật để lò xo dãn 5cm rồi thả nhẹ
A. Xác định Cơ năng, Động năng, Thế năng và vận tốc của vật khi lo xo giãn 3cm
B. Vật ma sát với sàn có Fms = 0.2N.Xác định vật tốc lúc vật đi qua vị trí lò xo không biến dạng
For Catherine Lumby, deciding to take on the role of breadwinner in her relationship was not a difficult choice. When she discovered she was pregnant with her first child, she had just been offered a demanding new role as Director of the Media and Communications department at the University of Sydney. But she didn't see this as an obstacle, and was prepared to use childcare when the children were old enough. It came, therefore, as a surprise to Lumby and her husband Derek that, after the birth of their son, they couldn’t actually bear the thought of putting him into childcare tor nine hours a day. As she was the one with the secure job, the role of primary care-giver fell to Derek, who was writing scripts for television. This arrangement continued for the next four years, with Derek working from home and caring for both of their sons. He returned to full-time work earlier this year.
Whilst Lumby and her husband are by no means the only Australians making such a role reversal, research suggests that they are in the minority. In a government-funded survey in 2001, only 5.5 percent of couples in the 30-54 year age group saw the women working either part- or full-time while the men were unemployed.
The situation is likely to change, according to the CEO of Relationships Australia, Anne Hollonds. She suggests that this is due to several reasons, including the number of highly educated women in the workforce and changing social patterns and expectations. However, she warns that for couples involved in role-switching, there are many potential difficulties to be overcome. For men whose self-esteem is connected to their jobs and the income it provides to the family, a major change of thinking is required. It also requires women to reassess, particularly with regard to domestic or child-rearing decisions, and they may have to learn to deal with the guilt of not always being there at key times for their children. Being aware of these issues can make operating in non-traditional roles a lot easier.
5. In paragraph 2, the word “reversal" is closest in meaning to ____.
A. stability B. modification C. rehearsal D. switch
EXERCISE 7: Complete the sentences with must, should, need, needn’t, can, could, may, might
1. In Britain many children ____________ wear uniform when they go to school.
2. That restaurant ______________ be very good. It’s always full of people.
3. I think the government ______________ do more to help homeless people.
4. We have plenty of time for doing the work. We ______________ be hurried.
5. You ______________ ring the bell; I have a key.
6. I ______________ get up early tomorrow. There are a lot of things I want to do.
7. You ______________ explain that again because I understand everything now.
8. I ________________ do that again. It’s my promise.
9. You _____________ take your umbrella along with you today. It ____________ rain later on this afternoon.
10. You _____________ have been absent from that important session.
Lập dàn ý
Nụ cười là chốn nghỉ ngơi cho người mệt mỏi, là ánh sáng cho người nản chí, là tia nắng cho người buồn tủi, là thuốc giải độc tốt nhất cho những hoài nghi, lo lắng và sợ hãi.
Anh chị có ý kiến gì về phát biểu trên? Hiểu biết này giúp ích gì cho bạn trong giao tiếp.
Giúp em với ạ, đề khó quá mà em sắp làm bài khảo sát.
Exercise 5
Two other in his argument for his country’s independence are worth a mention.
a. notices b. points c. effects d. reports
He’s such a naughty child; it’s amazing what his mother lets him away with.
a. go b. make c. do d. get
The factory paid nearly a million pounds to their employees who were injured in the explosion.
a. off b. out c. back d. in
Having the table, Mrs Roberts called the family for supper.
a. laid b. spread c. ordered d. completed
The little girl wouldn’t go into the sea her father went too.
a. except b. but c. also d. unless
“How can we out together what we’re to do if we never talk about it frankly?” she cried in desperation.
a. test b. find c. work d. search
Wild ducks always fly in a definite .
a. figure b. formula c. shape d. formation
Mike was the in his family; all his
others were much taller.
a. lowest b. shortest c. slightest d. littlest
You’ll yourself a lot of time if you take the car.
a. spend b. make c. save d. spare
I wrote to the company, them for a catalogue.
a. demanding b. asking c. enquiring d. applying
Exercise 6
Firemen rescued several people from the floor of the blazing building.
a. high b. top c. basement d. low
When the electricity failed, he a match to find the candles.
a. ru
ed b. scratched c. struck d. started
She put speaking to him as long as possible
a. off b. over c. away d. back
She wondered her father looked like now, after so many years away.
a. how b. whose c. that d. what
She her neighbor’s children for the
oken window.
a. accused b. complained c. blamed d. denied
He filled in the necessary forms and for the job.
a. appealed b. asked c. requested d. applied
He says he’s been to restaurant in town.
a. many b. every c. all d. most
She hasn’t written to me .
a. already b. yet c. never d. any longer
She is traveling to work by train today because her car is being .
a. stopped b.
oken c. serviced d. rented
He tried every key in turn but not fitted.
a. each b. one c. any d. none
Exercise 7
Her parents were very because she was out so late last night.
a. responsible b. so
y c. wo
ied d. overcome
After a lot of difficulty, he to open the door.
a. managed b. succeeded c. obtained d. realized
I have been looking for this book for month, and I have found it.
a. at last b. in time c. at the end d. at present
My employer’s of my work does not matter to me at all.
a. meaning b. belief c. opinion d. expression
The purpose of the examination was to the student’s knowledge.
a. try b. inspect c. prove d. test
I’ll have to to you, otherwise he will hear.
a. shout b. say c. whistle d. whisper
As soon as the fire-bell rang, everyone walked quickly downstairs and out of the building, gathered in the car park.
a. while b. then c. before d. to
There’s to be frightened of the dog; he’s quite harmless.
a. fear b. no fear c. no need d. any reason
After closing the envelope, the secretary the stamps on firmly.
a. licked b. sucked stuck d. struck
The teacher them the answer to the question.
a. explained b. told c. said d. discussed