Seven
<em><u>Formula</u></em>
I'm assuming that the formula used is
R = R_ref [1 + α*(T - T_ref)=
<em><u>Givens</u></em>
- R_ref is the starting resistance of 100 ohms
- α (alpha) = 4.0 *10^-4 or 0.00040
- T_ref = 11.5 degrees Celcius
- T = 10 degrees.
- R=??
<em><u>Solution</u></em>
R = 100[ 1 + 4.0*10^4(10 - 11.5)] Collapse the brackets.
R = 100[ 1 + 4.0*10^4(-1.5)] Simplify
R = 100[1 - 0.00060] Subtract
R = 100[0.9994] Multiply
R = 99.94
Answer: A
Eight
The accepted formula for resistance and resistivity is
R = ρ * A / L where
rho is the resistivity
A is the face Area of the conductor
L is the length of the conductor.
Now a perfect conductor has a resistance of 0.
So since resistivity is a direct variation with resistance, its value also has to be 0.
Answer: A
Nine
The formula you need for this is W = I^2* R
W = 14 Watts
R = 17 ohms
I = ??
14 = I^2 * 17 Divide bother sides by 17
14/17 = I^2
0.8235 = I^2 Switch and take the square root of both sides.
I = sqrt(0.8234)
I = 0.9075 Answer: D
For an object to be in equilibrium, it must be experiencing no acceleration. This means that both the net force and the net torque on the object must be zero.
Answer:
Mass of the larger object
This is called PARALLAX. Parallax is a displacement or difference in the apparent position of an object viewed along two different lines of sight, and is measured by the angle or semi-angle of inclination between those two lines.
