When you calculate the net electric field in a location due to the presence of more than one large charge (Q), it is generally not helpful to include the sign of the charges in the
equation for electric field. Why not? Specifically, what does the sign of a charge tell you about the direction of the electric field, and what does the sign of a charge NOT tell you
about the direction of the electric field?

1.) What is the Hall effect, give a real life example, list its applications.

2.) When an electric light bulb is operated on a low frequency AC, they noticeably flicker (for example 5Hz) why?

1. Use basic laws of physics to explain the following situations:

a. Spiderweb has a greater tensile strength than steel, yet you can snap a spider web very easily with your hand. Explain why this is so.

b. Use Bernoulli's Principle to explain how the shape of an airplane wing creates a "lift force."

c. Why is it easier to sew with a sharp needle than it is to sew with a dull one?

d. Describe how the speedometer of your car is able to tell how fast the car is going.

One billiard ball is shot east at 1.9m/s . A second, identical billiard ball is shot west at 0.90m/s . The balls have a glancing collision, not a head-on collision, deflecting the second ball by 90? and sending it north at 1.31m/s .

1.)What is the speed of the first ball after the collision?

2.)What is the direction of the first ball after the collision? Give the direction as an angle south of east.

is astronomy based on probability and chance? Are certain laws well defined, and verified through experimentation?

20 km east plus 10 km northeast

Moon effect. Some people believe that the Moon controls their activities. If the Moon moves from being directly on the opposite side of Earth from you to being directly overhead, by what percentage does (a) the Moon's gravitational pull on you increase and (b) your weight (as measured on a scale) decrease? Assume that the Earth–Moon (center-to-center) distance is 3.82 × 108 m, Earth's radius is 6.37 × 106 m, Moon's mass is 7.36 × 1022 kg, and Earth's mass is 5.98 × 1024 kg.

When a potential difference of 142 V is applied to the plates of a parallel-plate capacitor, the plates carry a surface charge density of 45.0 nC/cm2. What is the spacing between the plates?

I need an in depth, thorough explanation of static electricity and the relevant related topics!

A concave mirror (f = 44 cm) produces an image whose distance from the mirror is one-fourth the object distance. (a) Determine the object distance. cm (b) Determine the (positive) image distance. cm

Calculate the total kinetic energy of the reaction products in the reaction ¹³C(d,n)¹⁴N if the incident d particle has KE = 3000 keV?
(in MeV)

Two small nonconducting spheres have a total positive charge of 108.4uC. When placed 1.08m apart, the force each exerts on the other is 12.8N and is repulsive. What is the (larger) charge on the spheres? What is the smaller charge on the other sphere?

Calculate the moment of inertia of a baseball bat for the following cases. (a) Assume the bat is a wooden rod of uniform diameter and take the pivot point to be in the middle of the bat, at the end of the bat, and 5 cm from the end of the handle, where a batter who "chokes up" on the bat would place his hands. Hint: Consider the bat as two rods held together at the pivot point.

a) Estimate the mass of the bat.

m=.552kg

Estimate the length of the bat

estimated length= .75m

(i) in the middle of the bat (Use your estimate.)

(ii) at the end of the bat (Use your estimate.)

(iii) 5 cm from the end of the handle (Use your estimate.)

(b) Assume a realistic bat, which is narrower at the handle than at the opposite end, and consider the three locations from part (a). (i) The estimate from part (a) for the moment of inertia in the middle of the bat is which of the following?

a) too high, b)approximately equal, c) too low

(ii) The estimate from part (a) for the moment of inertia at the end of the bat is which of the following?

a) too high, b)approximately equal, c) too low

(iii) The estimate from part (a) for the moment of inertia 5 cm from the end of the handle is which of the following?

a) too high, b)approximately equal, c) too low

A homemade capacitor is assembled by placing two 9-in. pie pans 4cm apart and connecting them to the opposite terminals of a 6-Vbattery.

Part A:

Estimate the capacitance.

C= ?? V

Part B:

Estimate the charge on each plate.

Q= ?? C

Part C:

Estimate the electric field halfway between the plates.

E = V/m

Part D:

Estimate the work done by the battery to charge the plates.

W= ?? J

An open container holds ice of mass 0.565kg at a temperature of -13.5?C . The mass of the container can be ignored. Heat is supplied to the container at the constant rate of 740J/minute .

The specific heat of ice to is 2100 J/kg?K and the heat of fusion for ice is 334