Physics Answers

When a slab of insulating material is placed between the plates of a charged capacitor, the electric field becomes A. less B. similar C. greater D. depends on the situation 21. A capacitor has a charge of 0..02 C when connected with a 0 V battery. The capacitance is A. 1 µF B. 4 µF C. 2 µF D. 40 µF 22. A 50 µF has a potential difference of 8 V. What is its charge? A. 4 x 10-3 C B. 6.25 x 10-5 C C. 4 x 10-4 C D. 6.25 x 10-6 C 23. A parallel plate capacitor has an energy of 2.5 J. It must be placed in a potential difference of A. 150 V B. 350 V C. 500 V D. 0.25 MV

A typical incandescent bulb has an efficiency of about 10%. What current is needed for a bulb with a resistance of 1.5×10^2 Ω to output power of 6.0 W?

the distance between 2 atomic nucleus is 0.015m,calculate the atomic radier of the atom

If the atmospheric pressure is 108.2 kPa and the gage attached to the tank reads 192 mmHg vacuum, find the absolute pressure within the tank.

A uniform electric field of 500 N/C is established between two oppositely charged metal plates. A particle with a charge of +0.003 C is moved from the bottom (negatively charged) plate. The string is tied to the charged that is pulling it upward. The distance between the plates is 5 cm.

a.      What is the change in the potential energy of the charge?

b.      What is the change in electric potential from the bottom to the top plate? 

Ten kilograms of steam at 100

0C is condensed in 500 kg of water

at 40 0C. What is the resulting temperature? (Ans: 51.8 0C

In a 300-m race, runner A starts from rests and accelerates at 1.6m/s2

for the first 30 m and then runs

at a constant speed. Runner B starts from rests and accelerates at 2.0m/s2

for the first 30m and then

runs at a constant speed. Runner A begins running as soon as the race begins but B firsts takes a nap

to rest up. What is the longest nap that B can take and still not to lose the race?

An ion of charge, q=+1.60 x 10¹9 C entering a uniform magnetic field, B-0.3 T

with a velocity, v-6.5 x 10³ ms as shown in FIGURE 3(b). The mass of the ion is 1.76 x 107 kg.

Copy FIGURE 3(b). Sketch the path of the ion in the magnetic field.

[1 mark]

[6 marks]

Calculate the distance from the hole that the ion strikes the plate.

(ii)

(iii) Another ion of twice the mass but has the same charge and velocity enters. the magnetic field. Show on the same figure in (i) above, the path of this ion.

An electric heater is to be made from a

nichrome wire. Nichrome has a Resistivity of 1.0*10^-6 ohm'sm

at the operating temperature of

the heater. The power of the heater is 60W

when the potential difference across its

terminals is 12V. Calculate the length of the

wire of diameter 0.30mn required for the

heater.

Question #173223 in Physics

Given

Mass(a) = Mass(b)

V(a)1 = 6.2 m/s

V(a)2 = final velocity of the cue ball

V(b)1 = 0 m/s

V(b)2 = final velocity of the billiard ball

angle deflected of the billiard ball = 45° from the horizontal

x = angle deflected of the cue ball from the horizontal

6.2 m/s = (Va2){cos(x) + sin(x)}

In the x-direction

6.2 m/s + 0 m/s = (Va2)(cos x) + (Vb2)(cos 45)

The direction of the cue and billiard balls are the same because of the law of inertia.

In the y-direction

0 m/s + 0 m/s = (Va2)(sin x) + (-Vb2)(cos 45)

The final velocity of the billiard ball in the y-direction is negative because of the difference in the y-direction between the cue and billiard balls.

If we use substitution and elimination methods for two equations we can find 6.2 m/s = (Va2){cos(x) + sin(x)}.

However, I am having difficulty in the next sequence. In which part am I wrong? What is the solution? Do we have to use the formula of coefficient of restitution? I need your help. Thank you.