Answer: D) 3.2 × 10^8
Explanation: Insulators are best described as materials which are poor conductors of electricity and hence do not allow passage of electricity through them. Resistivity are hence used to describe property or characteristic of a material which does not allow the flow or passage of electric current.
In summary, materials which high resistivity values are referred to as Insulators. Conversely, those with low resistivity or high conductivity values are called conductors while those with intermediate values are named semiconductors.
In the question given above, the material with a resistivity value of 3.2 × 10^8 - - - has a very high resistivity value (320000000Ω), the other options given have very low resistivity values ; 0.0000000017, etc and are most likely to be conductors due to their excessively low resistivity values.
Answer:
the time of motion of the ball is 6.89 ms.
Explanation:
Given;
angular speed, ω = 38 rad/s
angular distance, θ = 15 degrees
Angular distance in radian;
Time of motion is calculated as;
Therefore, the time of motion of the ball is 6.89 ms.
Explanation:
The table is level and there are no other forces on the book, so the normal force is equal to the weight.
N = mg
N = (2.3 kg) (9.8 m/s²)
N = 22.5 N
It stops accelerating when the air resistance is equal to its weight.
That's (m•g)
= (2 kg) • (9.8 m/s^2)
= 19.6 newtons
