Consider the upward direction of motion as positive and downward direction of motion as negative.
a = acceleration due to gravity in downward direction = - 9.8 
v₀ = initial velocity of rock in upward direction = ?
v = final velocity of rock at the highest point = 0 
t = time to reach the maximum height = 4.2 sec
Using the kinematics equation
v = v₀ + a t
inserting the values
0 = v₀ + (- 9.8) (4.2)
v₀ = 41.2 
Answer:
microscopic means that they are very very tiny, you cannot see them with the human eye, you have to use a tool like a microscope
Explanation:
Answer:
m = 1.5 kg
Explanation:
Data:
- Aceleration (a) = 8 m/s²
- Force (F) = 12 N
- Mass (m) = ?
Use formula:
Replace in the formula:
Equate the newtons:
Simplify m/s²:
It divides:
What is the mass of the train?
The mass of the train is <u>1.5 kilograms.</u>
Well i think the best answer would be A