Answer:
C. At a particular instant
Explanation:
Speed is the defined as the ratio between the distance covered by an object and the time taken:

where d is the distance and t the time.
However, there are two possible measurements of speed:
- Average speed: this is the speed measured over a non-zero time interval (for example: a car moving 100 metres in 5 seconds; its average speed is

- Instantaneous speed: this is the speed of an object measured at a particular instant in time, so for a time interval that tends to zero. So, in the previous example, the average speed is 20 m/s but the instantaneous speed of the car at various instants of time can be different from that value.
Answer:
Correct answer: t = 2.86 seconds
Explanation:
We first use this formula
V² - V₀² = 2 a d
where V is the final velocity (speed), V₀ the initial velocity (speed),
a the acceleration and d the distance.
We will calculate the acceleration from this formula
a = (V² - V₀²) / (2 d) = (2.5² - 1²) / (2 · 5) = (6.25 - 1) / 10 = 5.25 / 10
a = 0.525 m/s²
then we use this formula
V = V₀ + a t => t = (V - V₀) / a = (2.5 - 1) / 0.525 = 1.5 / 0.525 = 2.86 seconds
t = 2.86 seconds
God is with you!!!
Answer:
sorry but I can understand the question
Answer: Gravitational force between the two masses does not depend on the medium separating two masses.