Answer:
Vf = 28 m/s
Explanation:
In order to find the final velocity of the rock, we will use the 3rd equation of motion. The third equation of motion for vertical direction is written as follows:
2gh = Vf² - Vi²
where,
g = acceleration due to gravity = 9.8 m/s²
h = height dropped = 40 m
Vf = final velocity of the rock = ?
Vi = Initial Velocity of the rock = 0 m/s (since, rock was initially at rest)
Therefore,
(2)(9.8 m/s²)(40 m) = Vf² - (0 m/s)²
Vf = √(784 m²/s²)
<u>Vf = 28 m/s</u>
The first living being to make an orbital spaceflight around the Earth was the dog Laika, aboard the Soviet spacecraft Sputnik 2 on 3 November 1957.
Answer;
3.45 × 10^-1
Explanation;
-Here we wish to write the number 0.345 as a coefficient times 10 raised to an exponent. To convert to scientific notation, start by moving the decimal place in the number until you have a coefficient between 1 and 10; here it is 3.45.
-The number of places to the left that you had to move the decimal point is the exponent.
= 0.345
= 3.45/10
= 3.45 × 10^-1
Answer:
v = 1/3 m / s = 0.333 m / s
in the direction of the truck
Explanation:
The average speed is defined by the variation of the position between the time spent
v = Δx / Δt
since the position is a vector we must add using vectors, we will assume that the displacement to the right is positive, the total displacement is
Δx = 20 - 15 +20
Δx = 25 m
therefore we calculate
v = 25/75
v = 1/3 m / s = 0.333 m / s
in the direction of the truck