Answer:
Explanation:
Calculate the volume of the lead

Now calculate the bouyant force acting on the lead


This force will act in upward direction
Gravitational force on the lead due to its mass will act in downward direction
Hence the difference of this two force

If V is the volume submerged in the water then bouyant force on the bobber is

Equate bouyant force with the tension and gravitational force

Now Total volume of bobble is

=
Answer:
magnification will be -0.025
Explanation:
We have given the radius of curvature = 12 cm
And object distance = 3 m
So focal length 
Now for mirror we know that
So 

v = 0.750 m
Now magnification of the mirror is 
<h2>
Answer: Pulsars</h2>
A <u>pulsar</u> is a neutron star that emits very intense electromagnetic radiation at short and periodic intervals ( rotating really fast) due to its intense magnetic field that induces this emission.
Nevertheless, it is important to note that all pulsars are neutron stars, but not all neutron stars are pulsars.
Let's clarify:
A neutron star, is the name given to the remains of a supernova. In itself it is the result of the gravitational collapse of a massive supergiant star after exhausting the fuel in its core.
Neutron stars have a small size for their very high density and they rotate at a huge speed.
However, the way to know that a pulsar is a neutron star is because of its high rotating speed.
Answer:
B: air pressure inside the car drops suddenly
Explanation:
Air in the car drops suddenly because the roof region has lowered pressure than the atmospheric pressure usually varying with the speed of the car