Homework for XI/group A/SHIKSHA/Saturday/29-09-2018

Q1.  A force of 200 N is applied to a block of mass 20 kg on an inclined plane at 53 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 ?

(iii) How much force is required to keep the body at rest on the inclined plane ?

Q2.  Write down some of the advantages and disadvantages of friction

Q3. A 20 kg block is initially at rest on a rough horizontal surface. A horizontal   force of 75 N is required to set the block in motion. After it is in motion, ahorizontal force of 60 N is required to keep the block moving  with constant speed. Find the coefficient of static  and kinetic friction .

Q4. A body of 5 kg weight kept on a rough inclined plane of angle 30º starts  sliding with a constant velocity. Then find the coefficient of friction . (assume  g = 10 m/s²)

Q5. Define the following terms

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

Homework for XII/group B/VIDYARTHI/Friday/28-09-2018

Q1. An AC is given as   i = 10 sin ωt  with .0.02 sec as time period . Draw the AC showing the mean value and RMS value .

Q2. Prove that mean value for the full cycle of an AC is zero .

Q3. The RMS voltage  of the power supply that we use in India is 220 volt . What will be it’s peak value ? Also find the mean value .

Q4. Why AC is dangerous ?

Q5.  An AC   i = 10 sin 314t  is connected to a resistor of resistance 10 Ω   . Find the potential drop across the resistor .

Q6.  An AC   i = 10 sin 314t  is connected to an inductor  of self induction of  10 Henry  . Find the potential drop across the inductor .

Q7.  An AC   i = 10 sin 314t  is connected to a capacitor of 10 μF   . Find the potential drop across the capacitorr .

Q8. Draw the graph showing the variation between

(I) inductive reactance and angular frequency

(ii) capacitive reactance and angular frequency

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

Science & Physics

Science, as we know, is built up with facts as a house is with bricks. But a collection of facts is no more a science than a pile of bricks is a house. Physics is the science of matter, energy, time, and space. Physics is an experimental science believing in the theories, proved by observations.

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