It makes it easier to dig a hole because it helps pick up dirt
Answer:
Resistance of gold wire, 
Explanation:
In this question we have given
Density of gold, 
resistivity of gold, 
Length of wire, 
Temperature, 
We know that relation between volume and density is given as

Therefore, volume occupied by one gram gold is given as,
.........(1)
We Know that Volume of gold wire which is cylindrical in shape is given by following formula
......(2)
Here,
...........(3)
here A is the cross sectional area of cylendrical gold wire
From equation 2 and 3
we got
...............(4)
on comparing equation 1 and equation 4, we got,



we know that resistance and resistivity are related by following formula,
................(5)
Put values of resistivity, A and L in equation 5, we got


Therefore resistance of gold wire, 
Answer:
Current needed = 704A
Explanation:
Using the fomula; torque(τ) = (I)(A)(B)Sinθ
Where B = uniform magnetic field
I = current and A = Area
Diameter = 19cm = 0.19m so, radius = 0.19/2 = 0.095m
Area(A) = πr^(2) = πr^(2)
= π(0.095)^(2) = 0.0284 m^(2)
Now, B(earth)= 5x10^-5 T
While, we can ignore the angle because it's insignificant since the angle of the wire is oriented for maximum torque in the earth's field.
Now, if we arrange the formula to solve for charge (I):
I = (τ)/(A)(B)
I = (1.0x10^-3) / (0.0284)(5x10^-5)
I = 704A
Answer:
45 j
Explanation:
At the top, the KE will have been converted to PE
KE = 1/2 mv^2 =PEat-top = 1/2 10 *3^9 = 45 j