Physics Answers

Two capacitors with 2.0 F and 3.0 F capacitance, respectively, are connected in series and subjected to a total potential difference of 100 V.

Find the

(a) total capacitance,

(b) charge stored in each capacitor, and

(c) potential difference across each capacitor.

You have five 10.0 F capacitors. Show all possible connections of all five capacitors to produce an equivalent capacitance of .5 F

Amultimodestep-indexfiberhascoreand cladding refractive indices of 1,475 and 1.458 respectively. If it has a core radius of 30 μm and operates at a wavelength of 1250 nm.

– What should be the core radius of the fiber if it is to operate as a single mode fiber

A wheel rotates with a constant angular acceleration of 3.5 rad/s². If the angular speed of the wheel is 2 rad/s at t = 0, Find what angle does the wheel rotate between t = 0 and t = 2 s ?

What is the maximum force on an aluminium particle with a +0.1 𝜇𝐶 of charge, which is passing between the poles of a 1.5 𝑇 permanent magnet at a speed of 5 𝑚𝑠−1? In what direction is the force?

Hint: Assume the direction of the magnetic field as preferred. Draw a diagram showing all the relevant vectors in terms of their components. Use the equation for the force on a moving charged particle in a magnetic field.

A cyclist cycles down a hill. At the top of the hill of height 50m he reaches a speed of 50ms-1. Calculate his speed at the bottom of the hill.

We have a horizontal spring with a mass attached oscillating with a maximum displacement of

A

on either side. At which intermediate displacement(s) the kinetic energy would equal the potential

energy [10]?

The first divers used metal ‘diving bells’ to move air under the water surface.

(a) Modelling the air in bell as a hemisphere with diameter of 2.5 metres, use the following information to calculate the upthrust produced due to the water.

Ρwater= 997 kgm^-3

Volume of a sphere = 4/3𝜋r³

g = 9.81 ms^-2

(b) If the bell was fully submerged and then its suspension cable was released, what would its maximum acceleration be, given that its mass was 4500 kg?

Given that the Young modulus of steel is 210 GPa, the extension of a steel wire undergoing a stress of 300x10⁶ Pa is equal to:

A) 0.14%

B) 1.4%

C) 14%

D) 140%

The speed of a ball bearing falling through treacle:

A) Decreases with distance fallen.

B) Increases with distance fallen and reaches a maximum.

C) Is constant.

D) Reaches a maximum and then decreases.