### Homework for XI / group B / Vidyarthi /Friday?28-09-2018

Q1.  A force of 200 N is applied to a block of mass 20 kg on an inclined plane at 37 º with the horizontal .

(i)  What will be the acceleration of the block in downward direction ?

(II) How much force is required to move it in up along the plane ?

Q2.  The coefficient of friction for a block of mass 10 kg and a surface is  0.3 .  Find the force of friction and the acceleration of the block if the applied force is 10 N , 30 N , 50 N and 0 N .

Q3. Explain why

(i) rolling friction helps in motion

(ii) static friction is a self adjusting force

Q4. State the laws of friction

Q5. Define the following terms

Sliding friction , limiting friction , angle of friction , coefficient of kinetic friction , angle of repose .

### Welcome

Hello students!

I have started my new blog named physics 365.com , which was earlier the name of my website . Due to some technical issues I have to repair that website and in place of it , starting this blog to interact with you.

You can ask your questions and doubts . I will definitely try to give you the answer.

I regularly submit the home works for my different batches at my institution named VIDYARTHI and SHIKSHA .

Hope you will cooperate .

Yours

Tridib sir
dated 28th September 2018

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