A capacitor is constructed out of two 1€ coins facing each other in air at a distance of 0.5mm and connected to a voltage source of Vs = 9V. Note: € is the symbol of the European currency as $ is the symbol of the US currency. The permittivity of vacuum is ε0 = 8.854-10-12 F m' The relative permittivity of distilled water is εr = 80. What is the formula to find the energy stored in the capacitor? W = CV-2 W = CV² ○ W = (CV)² W = CV-2 W = V² ○ W = (CV)-2 ○ W = CV2 ○ W = V-2

2. A bank of nickel-cadmium cells is used as the emergency lighting supply for a hospital. There are 100 cells connected in series and each has an A-hr rating of 120 A-hr. The bank has to be replaced, and the manufacturer is no longer supplying nickel-cadmium cells. It is decided to replace the cells with lead-acid cells. How many lead-acid cells will be required if each has an A-hr rating of 60 A-hr, and how should they be connected?

Answer the following with illustration and solutions.

Give 15 Electrical Components and Materials that can be found in every houses. Briefly explain its functions.

I. 22 2 5V find Fi&fz

A. In the morning, the student plugs in a computer (240 W) to study physics, a microwave (800 W) to make breakfast, and a hair dryer (1200 W) to dry the hair. What is the overall current in this student's room, in Ampere?   B. A circuit in a student’s room has a 15 A circuit breaker. In the morning, the student plugs in a computer (240 W) to study physics, a microwave (800 W) to make breakfast, and a hair dryer (1200 W) to dry the hair. Will this be enough to trip the circuit breaker?     not enough information     no, because the overall current is more than 15 A     no, because the overall current is less than 15 A     yes, because the overall current is less than 15 A     yes, because the overall current is more than 15 A

Find the upper limit (in ohms)for the :give color code Grey Blue Red Gold اخترأحد الخيارات a. 9.030K b. None of these c. 9030K d. 8500

Calculate the approximate output power of a PV cell with the area of 10cm*10Cm? a. 150W b. 1.5W c. 0.15W d. 15W

A battery consists of four cells connected in parallel, each having an emf of 24 volts and resistances of 0.40, 0.45, 0.42, 0.46 Ohm. A resistance of 1.50-Ohm is connected across the terminals of the battery. Determine: current; terminal voltage; current in each cell; Efficiency of the system.

The size of a bacteria is 0.25 micrometer. This size is same as a. 250 nm b. 25nm c. 2.5 nm d. 0.0025nm