Answer:
2.28 s
Explanation:
Let g = 9.8 m/s2 and neglect air resistance. The box of sand with an initial velocity of 4.2m/s in free fall would yield the following equation of motion
t = 2.28 or t = -3.14
Since t can only be positive we will pick t = 2.28
s
Answer:
Laurens suv have been travelling 60km/h speed if she can covers the distance of 10 kilometers in 5 minutes.
Explanation:
As per the given question,
Distance = 10 km
Time = 5 minutes
Convert minutes into hour.
There are 60 minutes in one hour, hence 5 minutes in hours is written as
We know the relationship between distance, speed and time is as follows,
Speed = 120km/h
Laurens suv exceeds the limit by = 120 – 60
Thus the speed limit exceeds by 60km/h
.
No, newton’s second law does not apply to a situation in which there is no net force.
<h3>
What is force?</h3>
A force is a push or pull upon an object which stops or tends to stop the object and move or tends to move an object.
No, newton’s second law apply to a situation in which there is no net force because force compels the object to move in the direction in which force is applied so we can conclude that force is compulsory to move an object.
Learn more about force here: brainly.com/question/12970081
Answer:
Wegener first thought of this idea by noticing that the different large landmasses of the Earth almost fit together like a jigsaw puzzle. The continental shelf of the Americas fits closely to Africa and Europe, and other continents showed the same trend. Wegner also analyzed both sides of the Atlantic Ocean for rock type, geological structures and fossils and noticed that there was a significant similarity between matching sides of the continents, especially in fossil plants.
In physics, there are already derived equation that are based on Newton's Law of Motions. The rectilinear motions at constant acceleration have the following equations:
x = v₁t + 1/2 at²
a = (v₂-v₁)/t
where
x is the distance travelled
v₁ is the initial velocity
v₂ is the final velocity
a is the acceleration
t is the time
Now, we solve first the second equation. Since it mentions that the car comes eventually to a stop, v₂ = 0. Then,
-5 = (0-v₁)/t
-5t = -v₁
v₁ = 5t
We use this new equation to substitute to the first one:
x = v₁t + 1/2 at²
15 = 5t(t) + 1/2(-5)t²
15 = 5t² - 5/2 t²
15 = 5/2 t²
5t² = 30
t² = 30/5 = 6
t = √6 = 2.45
Therefore, the time it took to travel 15 m at a deceleration of -5 m/s² is 2.45 seconds.
