Answer:
Density = Mass/volume. D= 60/30.Divide it and you'll get ur answer as 2
Explanation:
As per Rayleigh criterion, the angular resolution is given as follows:

From this expression larger the size of aperture, smaller will be the value of angular resolution and hence, better will be the device i.e. precision for distinguishing two points at very high angular difference is higher.
Answer:
1.2 amps :)
Explanation:
A heater has a resistance of 10.0 Ω. It operates on a 12.0 V. What is the current through the resistor?
Known:
Unknown:
I = V/R
= 12.0 V / 10.0 Ω
= 1.2 amps
Answer and Explanation:
This experiment is known as Lenz's tube.
The Lenz tube is an experiment that shows how you can brake a magnetic dipole that goes down a tube that conducts electric current. The magnet, when falling, along with its magnetic field, will generate variations in the magnetic field flux within the tube. These variations create an emf induced according to Faraday's Law:

This emf induced on the surface of the tube generates a current within it according to Ohm's Law:

This emf and current oppose the flux change, therefore a field will be produced in such a direction that the magnet is repelled from below and is attracted from above. The magnitude of the flux at the bottom of the magnet increases from the point of view of the tube, and at the top it decreases. Therefore, two "magnets" are generated under and above the dipole, which repel it below and attract above. Finally, the dipole feels a force in the opposite direction to the direction of fall, therefore it falls with less speed.
Answer:

Explanation:
For the cat to stay in place on the merry go round without sliding the magnitude of maximum static friction must be equal to magnitude of centripetal force

Where the r is the radius of merry-go-round and v is the tangential speed
but

So we have

Substitute the given values
So
