Answer:
12500W
Explanation:
Given parameters:
Work done = 250000J
Time taken = 20s
Unknown:
Power of the crane = ?
Solution:
Power is the defined as the rate at which work is being done;
Mathematically;
Power = 
insert the parameters and solve;
Power = 
= 12500W
Answer:
A conservative force is a force with the property that the total work done in moving a particle between two points is independent of the path taken Equivalently if a particle travels in a closed loop the total work done by a conservative force is zero
Explanation:
The correct answer is:
<span>2. sound intensity is a more objective and physical attribute of a sound wave because loudness can vary from person to person
indeed, sound intensity is a measurable quantity, and so it is objective, while loudness is the subjective perception of the sound level, so it varies from person to person.</span>
<u>Answer:</u>
Prior to exercise, a proper warm-up of 10-15 minutes is extremely important to avoid injuries.
- Don't go too hard in the beginning and boost your activity level slowly. A good indication of a proper warm-up is that you feel sweat on your body parts.
- Don't overstretch right in the beginning as it can cause sore in your muscles and joints or stress fractures.
- Take a break if you feel sick or fatigues and use other drinks along with water to replace electrolytes and body fluids.
Answer:
Centripetal Acceleration 18.75 m/s^2, Rotational Kinetic Energy 843.75 J
Explanation:
a Linear acceleration (we cant find tangential acceleration with the givens so we will find centripetal)
a= ω^2*r
ω= 300rev/min
convert into rev/s
300/60= 5rev/s
a= 18.75m/s^2
b) use Krot= 1/2 Iω^2
plug in gives
1/2(30*2.25)(25)= 843.75 J
