Answer:
u=speed, w=wavelenght, f=frequency
It's known that u=w*f => f=u/w
u=20m/s ==> f=20/0,5 => f=40 Hz
w=0,50m
Explanation:
Answer:

Explanation:
Using the conservation of energy we have:

Let's solve it for v:

So the speed at the lowest point is 
Now, using the conservation of momentum we have:

Therefore the speed of the block after the collision is 
I hope it helps you!
Answer:
Dry lubricants or solid lubricants are materials that, despite being in the solid phase, are able to reduce friction between two surfaces sliding against each other without the need for a liquid oil medium.
Explanation:
Answer:
Explanation:
I-V graph always represent a straight line
Answer:
Current will be 81.7 mA
Which is not given in bellow option
Explanation:
We have given capacitance 
Resistance R = 500 ohm
Voltage V = 12 volt
We know that time constant of RC circuit of RC circuit is given by

Time is given as t = 1 sec
We know that current in RC circuit is given by

So current 
Which is not given in the following option