Top answers

What happens to the pressure inside a gas-filled ball when the temperature is increased? Explain your answer, stating the assumption made.

From definition of pressure have P=F/A (in reality for a ball we are talking about infinitesimal areas, but the general definition is sufficient at this level). Assume that the area of the surface under cons...
JH
Answered by James H. • Physics tutor
2551 Views

How do I approach this question? Our teacher never explained it in class!

Any question in physics will boil down to a simple conservation law, even at the relatively difficult A level exams. Basically, in order to successfully solve this question, you need to identify 3 key things...
FP
2297 Views

What is dimensional analysis and how is it used?

When one is faced with a problem requiring derivation of an equation, they might be asked to use dimensional analysis . This is a concept that involves analyzing the units of known quantities (usually it is ...
CI
Answered by Christina I. • Physics tutor
3037 Views

Steel has a density of 8030kg/m^3. Show that a steel ball with a diameter of 5cm weighs approximately 5N

Using Weight = mass*gravitational strength Using: Mass = density * volume Using Volume = (4/3) pi r 3 Radius = 2.5cm = 0.025m Volume = (4/3) pi 0.025 3 = 0.00006544 m 3 (to 4 siginificant figures) Mass = 803...
SH
Answered by Sameh H. • Physics tutor
13722 Views

What is the total energy of a spaceship of mass m, orbiting a planet of mass M in a circular orbit with radius r? The ship and the planet are taken to be an isolated system.

In the non-inertial frame of reference of the spaceship, a centrifugal and a gravitational force acts on the spaceship. If its mass is m and the positive direction is radially outwards, we have: F G = -GmM/r...
ID
Answered by Ivan D. • Physics tutor
3350 Views