Answer:
acceleration or a deceleration
Explanation:
The gradient of a position - time graph represent the velocity.
a straight line indicate a constant velocity (gradient ≠ 0)
when it is a parallel line to the time axis , it indicated no movement
when it is a curved line it indicates a changing velocity (either acceleration or a deceleration) as mentioned in the graph
Answer:
D, the acceleration of A is twice that of b.
Explanation: in four seconds b got to ten, in two seconds a got to 20. Going 10m/s faster in half the time is going twice the acceleration
Answer:
The star is at a distance of 100 parsecs.
Explanation:
The distance can be determined by means of the distance modulus:
(1)
Where M is the absolute magnitude, m is the apparent magnitude and d is the distance in units of parsec.
Therefore, d can be isolated from equation 1

Then, Applying logarithmic properties it is gotten:
(2)
The absolute magnitude is the intrinsic brightness of a star, while the apparent magnitude is the apparent brightness that a star will appear to have as is seen from the Earth.
Since both have the same spectral type is absolute magnitude will be the same.
Finally, equation 2 can be used:
Hence, the star is at a distance of 100 parsecs.
Key term:
Parsec: Parallax of arc seconds
Impulse describes the change of momentum. Since we don't know the momentum of the soccer ball before the hit, this question is hard to answer. If you assume the momentum of the ball before the hit was p = 0, then the change in momentum is just Δp = Impulse = mv.
Answer:
a loud explosive noise caused by the shock wave from an aircraft traveling faster than the speed of sound.
Explanation: