Average speed = total distance / total time
total distance = 40 + 20 = 60km
total time taken = 10 + 5 = 15 minutes
Average speed = 60/15 = 4km/min
Answer:
1250 J
Explanation:
Work is said to be done when a force causes an object to move over a distance. The amount of work done (W) is calculated by multiplying the force by the distance traveled.
That is;
W = F × d
Where;
W = work done (J or N/m)
F = force (N)
d = distance (m)
Based on the information provided in this question, F = 5000N, d = 0.25m
Hence;
W = F × d
W = 5000 × 0.25
W = 1250J
Therefore, 1250Joules of work is done by the jack.
A screw driver rusting when left in a pail of water is a chemical reaction
Answer:
The answer is below
Explanation:
Newton's law of gravity states that the force between two bodies is directly proportional to the product of their masses and inversely proportional to the square of the distance between them. The law is expressed by the formula:

The masses and distances for this question is in common units, Therefore the result would be in ratios
a) 4 MEarth / 2 MSolar / 3 AU
The force (F) = (4 * 3) / 3² = 4/3
b) 1 MEarth / 1 MSolar / 1 AU
The force (F) = (1 * 1) / 1² = 1
c) 1 MEarth / 2 MSolar / 2 AU
The force (F) = (1 * 2) / 2² = 1/2