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what is the derivative of x?

Apply differentiation through first principles and understand the first principles to find the derivatives of common functions.

Answered by Yashvini S. • Physics tutor

2134 Views

When is a system in equilibrium?

A system is in equilibrium when there is no resultant force and no resultant torque (or moment). A moment is the turning effect of applying a force on a body. It is the product of the force and the perpen...

Answered by Razvan T. • Physics tutor

3452 Views

On a pirate ship, a 1.6m plank is held at one end to the ship. A 65kg pirate walks the plank with his 1.1kg parrot following 40cm behind him. What is the total clockwise moment acting on the plank when the pirate reaches the end of it?

Moment = force x distance

Pirate:

force = 65 x 9.81 =637.65

distance = 1.2

moment = 637.65 x 1.6 =1020.24 = 1020 Nm (3 sig fig)

Parrot:

force = 1.1x 9.81 = 10.79...

Answered by Amy S. • Physics tutor

2069 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)pir³

Radius = 2.5cm = 0.025m

Volume = (4/3)pi0.025

Answered by Sameh H. • Physics tutor

12367 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...

Answered by Ivan D. • Physics tutor

2734 Views