Imagine a ball is moving on the following horizontal line.
. . . . . . . . . . . . . . . . . . . O. . . . . . . . . . . . . . . . . .
Take right as positive. O is the starting point of the ball. Denote the ball by o.
. . . . . . . . . . . . . . . . . . . O. . . . . . . ... . . o . . . . . .
Assume the ball is moving to the right. It has positive displacement since it is on the right of O, and positive velocity since its positive displacement is increasing.
.ñ
. . . . . . . . . . . . . . . . . . . O. . . . o . . . . . . . . . . . . .
Now the ball is returning to O. It still has positive displacement since its current position is still on the right of O. However, its velocity is negative since its positive displacement is decreasing and the direction of the velocity vector points left, which is the negative side.
By now you should be able to come up with a scenario where the ball has negative displacement and positive velocity.
You can observe the same phenomenon in daily life. Say, as a stretched spring bounces to its starting position, if we let the returning direction be positive, the string has negative displacement since it is on the negative direction, but has positive velocity. Bungee jump can also used to illustrate the phenomenon.
<h2>
Energy used by heater is 8.21 x 10⁶ J</h2>
Explanation:
Energy = Power x Time
Power = Voltage x Current
Voltage = 120 V
Current = 9.5 A
Power = Voltage x Current
Power = 120 x 9.5 = 1140 W
Time = 2 hours = 2 x 60 x 60 = 7200 s
Energy = Power x Time
Energy = 1140 x 7200
Energy = 8208000 J
Energy used by heater is 8.21 x 10⁶ J
Answer:Visible light is a small part of the electromagnetic spectrum. The spectrum covers everything from gamma rays, x-rays, visible light, infrared, microwave and radio waves. Each part of the spectrum, including the different colors of visible light, have different wavelengths (the space between each wave).
Explanation:
Answer:
<em>1,378.9ms²</em>
Explanation:
Given the following
Distance S = 70.6m
Time t = 0.32secs
Initial velocity = 0m/s
Required
Acceleration
Using the equation of motion
S = ut+1/2at²
Substitute
70.6 = 0+1/2a(0.32)²
70.6 = 0.0512a
a = 70.6/0.0512
a = 1,378.9
<em>Hence the acceleration is 1,378.9ms²</em>
V = u + at where u is initial velocity (15 m/s), a is acceleration (2m/s^2) and t is time (15 seconds)
V = 15 + 2 X 15
V = 45 m/s
