Recall the formula,
∆<em>θ</em> = <em>ω</em>₀ <em>t</em> + 1/2 <em>α</em> <em>t</em> ²
where ∆<em>θ</em> = angular displacement, <em>ω</em>₀ = initial angular speed (which is zero because the disk starts at rest), <em>α</em> = angular acceleration, and <em>t</em> = time. Solve for the acceleration with the given information:
50 rad = 1/2 <em>α</em> (5 s)²
<em>α</em> = (100 rad) / (25 s²)
<em>α</em> = 4 rad/s²
Now find the angular speed <em>ω </em>after 3 s using the formula,
<em>ω</em> = <em>ω</em>₀ + <em>α</em> <em>t</em>
<em>ω</em> = (4 rad/s²) (3 s)
<em>ω</em> = 12 rad/s
Answer: 80N (choice #4)
Explanation: The force of gravity is proportional to the inverse of the square of the distance. That means, if the distance is cut in half, the square of that is 1/4, and the inverse of that is a factor 4. So the force increases by a factor of 4. Given that the force is 20N, the new force will be 4*20N=80N.
Examples of non ohmic materials are tungsten filament (bulb), diode,thermistors, crystal rectifiers and vacuum tube.
Answer:
<h2>320</h2>
Just use F =ma where m is mass and a is acc.