Answer:
a. 0.21 rad/s2
b. 2.205 N
Explanation:
We convert from rpm to rad/s knowing that each revolution has 2π radians and each minute is 60 seconds
200 rpm = 200 * 2π / 60 = 21 rad/s
180 rpm = 180 * 2π / 60 = 18.85 rad/s
r = d/2 = 30cm / 2 = 15 cm = 0.15 m
a)So if the angular speed decreases steadily (at a constant rate) from 21 rad/s to 18.85 rad/s within 10s then the angular acceleration is
b) Assume the grind stone is a solid disk, its moment of inertia is
Where m = 28 kg is the disk mass and R = 0.15 m is the radius of the disk.
So the friction torque is
The friction force is
Since the friction coefficient is 0.2, we can calculate the normal force that is used to press the knife against the stone
The correct answer is C) type of medium. Electromagnetic waves travel faster in solids than in liquids, and faster in liquids than in gases.
Answer:
heat came from the supernova that led to the formation of solar system
As it was explained in the Introductory Article on the Electromagnetic Spectrum, electromagnetic radiation can be described as a stream of photons, each traveling in a wave-like pattern, carrying energy and moving at the speed of light. In that section, it was pointed out that the only difference between radio waves, visible light and gamma rays is the energy of the photons. Radio waves have photons with the lowest energies. Microwaves have a little more energy than radio waves. Infrared has still more, followed by visible, ultraviolet, X-rays and gamma rays.
That should be able to help answer your question :)
According to Charles law, we know, at constant pressure, volume is directly proportional to temperature.
So, <span>V/T = constant
</span>
V₁/t₁ = V₂/t₂
V₁t₂ = V₂t₁
Here, we have: V₁ = 9 mL
V₂ = ?
T₂ = 50+272 = 323 K
T₁ = 19+273 = 292 K
Substitute their values into the expression:
9 × 323 = V₂ × 292
V₂ = 2907 / 292
V₂ = 9.95
After rounding-off to unit place value, it would be equal to 10 mL
So, In short Option C would be your correct answer.
Hope this helps!
