Explanation:
Can be safer and cheaper than the real world. Able to test a product or system works before building it. Can use it to find unexpected problems. Can speed things up or slow them down to see changes over long or short periods of time.
.
.
.
.
Answer:
s=800 m
Explanation:
Given that,
Acceleration of a runner, a = 4 m/s²
Time, t = 20 seconds
We need to find the distance covered by her. Initially, she was at rest. It means its initial velocity is equal to 0. So, using second equation of motion as follows :

Herre, u = 0

So, she will cover a distance of 800 m.
The answer to the first question is that plants make glucose and oxygen by taking in CO2 and H20.
The answer to the second question is having a heavier mass increases the force of a moving object. That is the Second Law of Motion, F = ma.
Answer:

Explanation:
Given data:
mass of sphere is 10 g
Angle between string and vertical axis is 
thickness of string 300 mm = 0.3 m

r =0.3 sin 13 = 0.067 m






q = ne


Answer:
the average speed of the car is 170 mph.
Explanation:
Given;
initial speed, u = 70 mph
time of motion, t₁ = 3 hours
final speed, v = 20 mph
time of motion, t₂ = 2 hours
The average speed of the car is calculated as;

Therefore, the average speed of the car is 170 mph.