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.
DescriptionElectric charge is the physical property of matter that causes it to experience a force when placed in an electromagnetic field. There are two types of electric charge: positive and negative. Like charges repel and unlike attract. An object with an absence of net charge is referred to as neutral.
Answer: D) a stone lies on the ground
Explanation:
Potential energy this is defined as the mechanical energy, energy stored, or energy created by the position of an object. Example; energy possessed by a ball while hanging at the top of a steep hill when about to roll down is called a potential energy. This is same as a stone which lies in a floor.
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