Answer:
1. 
2. 
Explanation:
Given:
length of copper cable, 
diameter of copper cable, 
current through the copper wire, 
We have the resistivity of copper, 
<u>We know that the resistance of a wire is given as:</u>
where:
cross sectional area of the wire
1.
<u>Now from the Ohm's law:</u>
2.
<u>From the Joules law the thermal energy generated as an effect of electrical energy is mathematically given as:</u>
<u />
where:
time duration for which the current flows
(∵ we have 3600 seconds in 1 hour)
Mass is that quantity that is solely dependent upon the inertia of an object. The more inertia that an object has, the more mass that it ha
Explanation:
It is known that the relation between speed and distance is as follows.
velocity = 
As it is given that velocity is 6 m/s and distance traveled by the bear is (d + 29). Therefore, time taken by the bear is calculated as follows.
............. (1)
As the tourist is running in a car at a velocity of 4.2 m/s. Hence, time taken by the tourist is as follows.
............. (2)
Now, equation both equations (1) and (2) equal to each other we will calculate the value of d as follows.
= 
4.2d + 121.8 = 6d
d = 
= 67.66
Thus, we can conclude that the maximum possible value for d is 67.66.
It's because lightbulbs need to carry an electric current within a range of resistance so that the material doesn't without breaking down.
Given parameters:
Frequency of the wave = 1520kHz = 1520 x 10³Hz
Unknown:
Wavelength of the radio photon = ?
Energy of the wave = ?
Solution:
The wavelength of any electromagnetic wave can found using the expression below;
C = f x ∧
Where C is the velocity of light = 3 x 10⁸m/s
f is the frequency of the wave
∧ is the wavelength
Since the unknown is ∧, input the known parameters and solve for it;
3 x 10⁸ = 1520 x 10³ x ∧
Wavelength = 
Wavelength = 
Wavelength = 1.97 x 10²m
ii. Energy of the wave;
Energy of a wave = hf
where h is the planck's constant = 6.63 x 10⁻³⁴ J Hz⁻¹
f is the frequency of the wave
Input the parameters and solve;
Energy of the wave = 6.63 x 10⁻³⁴ x 1.52 x 10⁶
= 10.1 x 10⁻²⁸J
The energy of this wave is 10.1 x 10⁻²⁸J
