Answer:
The heat may have stopped being added, because the heat is exactly what is causing the change. There are horizontal lines because of that, and when the heat resumes, the line peaks up.
Explanation:
1.Record her observation with the time it was hot.
2. Gather info about the pavement and its surroundings. Find out what it's made of and what its temp. is at different times of the day.
3. Come up with a hypothesis about why it is hot.
4. Design an experiment to test the hypothesis. If she thinks the Sun is responsible (which she should b smart enough to know), keep it covered during the day time and check it's temp.
5. Come up with a conclusion. If her hypothesis is not supported, design a new experiment or gather more info.
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:
Vx = 3.10 [m/s]
Vy = 11.59 [m/s]
Explanation:
To solve this problem we must decompose the velocity vector by means of the angle on the horizontal.
v = 12 [m/s]
Vx = 12*cos (75) = 3.10 [m/s]
Vy = 12*sin (75) = 11.59 [m/s]
