Other Physics Answers

A gas at a volume of V₀ in a container at pressure P₀ is compressed to one-fifth of its volume. What will be its pressure if the magnitude of its original temperature T is constant?

4. Aside from mobile phones that use radio waves to carry signals, list down atleast five other uses of radio waves to communicate and deliver messages.

3. What do you think is the role of telecommunications compsny in the delivery of information?

A 50 capacitor , a 0.3 H inductor and an 80 Ω resistor are connected in series with a 120 V, 60 Hz power source. 

(1)What is the impedance of the circuit?

(2)How much current flows in the circuit?

What is the power factor?(2 marks)

(3)How much power is dissipated by the circuit?

(4)What must be the minimum rating in volt-amperes of the power source?

Direction. Explain the following.

1. What is the relationship between the electric field E and the electric potential

V between the plates of the capacitor? Explain.

2. Where is the energy stored in a parallel-plate capacitor? Explain.

3. Let the energy stored “in the capacitor” be U. Show that U is given by the

expression: U = 1

2

Q2

/C

[Hint: The power P in the capacitor is given by P = 𝑑𝑈

𝑑𝑡

= IV where I = 𝑑𝑄

𝑑𝑡

. This is

a simple exercise on integration.]

A transformer has 1000 turns on its primary side which uses a 120 V AC source. If the transformer is used to produce 10 W of power at 12.0 V on the secondary side, and losses are negligible, determine:

a) the number of turns on the secondary side. b) the current on the secondary side.

 Convert (a) 50 rev to radians, (b) 48 rad to revolutions, (c) 72 rps(revolutions per second) to degree/s, (d ) 1.50 x 10³ rpm (revolution per minute) to rad/s,

Obtain ehrenfests theorem describing second order phase transition

The horn of Ms Brown’s VW has a frequency of 400 Hz. What frequency would her 3U math class hear if she honks the horn while driving at 50 km/h on a 23 C day?

a) toward the class

b) away from the class

760 J of heat is used to increase the temperature of 400g of copper block from 30 ℃ to 35 ℃. What is the specific heat capacity of the copper block?