Many people think it is very exciting and admirable(令人羡慕的) to be an actor. The actors often wear the most beautiful and fashionable clothes and they can make a lot of money. Many people like them and they have so many fans. But in fact, the job of an actor can be very tiring and hard. To make good movies, for example, action movies, the actors need to go to some remote(偏远的) places. There they don't have good places to stay or nice food to eat. They often have to get up early and go to bed very late. When they are too busy, they don’t have time to sleep or relax. It's very hard.

半径为1m的圆中，60°的圆心角所对的弧的长度为（　　）m．

一个人体检时站在磅秤上，秤的示数是50kg，这时人受到的重力大小是____ N，方向是____ ，这个力的施力物体是____ ．（g="10N/kg" ）