Explanation:
Dark Energy. Dark Energy is a hypothetical form of energy that exerts a negative, repulsive pressure, behaving like the opposite of gravity. It has been hypothesised to account for the observational properties of distant type Ia supernovae, which show the universe going through an accelerated period of expansion
<span>We put a motion detector at </span>one end of the track<span> and put a cart on the track. ... Next, we put a motorized fan on the cart and let it push the cart down the track. ... This is what I would expect based on the velocity graph, since </span>acceleration<span> equals the slope of the velocity graph, which remains</span>constant<span> in time.</span>
Answer:
(a) 
(b) 
Explanation:
Hello.
(a) In this case since the car is moving at an initial velocity of 18 m/s due north, the final velocity is computed considering the acceleration as positive since it is due north as well:

(b) In this case, since the car is moving due north by the acceleration is due south it is undergoing a slowing down process, thereby the acceleration is negative therefore the final velocity turns out:

Best regards.
Answer:
15.3 m/s
Explanation:
Radius of orbit= 6400+6300 = 12700 km
Circumference of orbit= 2*(22/7)*12700 =79796.45*10^3 m
Now,
Speed= Distance / Time
= 79796.45*10^3/(24*60*3600)
= 15.3 m/s
The distance starting from the point to the lighthouse would be regarded as the hypotenuse.
And also will be the radius of the circle the beam of light is generating at that point.
So get the radius first
r = sqrt (1^2 + 5^2)
r = 5.099 km
find the circumference:
C = 2*pi * 5.099 km
C = 2 * 16.01898094
C = 32.04 km
Then find the speed in km/sec
One revolution: 60/2 = 30 sec per revolution
Speed = 32.04 km/30 sec
S = 1.068 km/sec is the speed of light