Answer:
E) She can perform no measurement to determine this quantity.
Explanation:
A spacecraft is a machine used to fly in outer space.
According to Isaac Newton's third law of motion, every action produces an equal and opposite reaction. When fuel is shoot out of one end of the rocket, the rocket moves forward for which no air is required.
As Leah is moving in a spaceship at a constant velocity away from a group of stars, she cannot measure to determine this quantity.
Answer: B) 2.5 m/s
Explanation: Find the average of the time and distance, and see how far they go in only 1 second.
1 + 2 + 3 + 4 + 5 = 15
15 divided by 5 = 3
3 seconds
2 + 5 + 7 + 10 + 12 = 36
36 divided by 5 = 7.2
7.2m per 3 seconds.
7.2 divided by 3 = 2.4
Therefore, the answer is technically 2.4m/s
The value of 'g' is not affected by rotation at any place on Earth.
Answer:
Current, I = 0.0011 A
Explanation:
It is given that,
Diameter of rod, d = 2.56 cm
Radius of rod, r = 1.28 cm = 0.0128 m
The resistivity of the pure silicon, ![\rho=2300\ \Omega-m](https://tex.z-dn.net/?f=%5Crho%3D2300%5C%20%5COmega-m)
Length of rod, l = 20 cm = 0.2 m
Voltage, ![V=1\times 10^3\ V](https://tex.z-dn.net/?f=V%3D1%5Ctimes%2010%5E3%5C%20V)
The resistivity of the rod is given by :
![R=\rho\dfrac{L}{A}](https://tex.z-dn.net/?f=R%3D%5Crho%5Cdfrac%7BL%7D%7BA%7D)
![R=2300\ \Omega-m\dfrac{0.2\ m}{\pi (0.0128\ m)^2}](https://tex.z-dn.net/?f=R%3D2300%5C%20%5COmega-m%5Cdfrac%7B0.2%5C%20m%7D%7B%5Cpi%20%280.0128%5C%20m%29%5E2%7D)
R = 893692.30 ohms
Current flowing in the rod is calculated using Ohm's law as :
V = I R
![I=\dfrac{V}{R}](https://tex.z-dn.net/?f=I%3D%5Cdfrac%7BV%7D%7BR%7D)
![I=\dfrac{10^3\ V}{893692.30\ \Omega}](https://tex.z-dn.net/?f=I%3D%5Cdfrac%7B10%5E3%5C%20V%7D%7B893692.30%5C%20%5COmega%7D)
I = 0.0011 A
So, the current flowing in the rod is 0.0011 A. Hence, this is the required solution.