A chemical change. chemical changes could cause changes in shapes or sizes
The roughness of the surface should be varied by the students tp test the hypothesis in the best possible way.
Explanation:
As the hypothesis stated the relation between roughness of the surface and the distance covered by the marble, students first need to find the independent variable among these two. The independent variable will be the one which will not depend on the result of the other variable. But there will be change in the dependent variable on changing the independent variable.
So here the independent variable is the roughness of the surface as per the hypothesis. And the dependent variable will be distance covered by the marble.
So the students should vary the independent variable and check for desired changes in the dependent variable for confirmation of hypothesis.
Thus, the roughness of the surface should be varied by the students tp test the hypothesis in the best possible way.
The equation that relates distance, velocities, acceleration, and time is,
d = V₀t + 0.5gt²
where d is distance,
V₀ is the initial velocity,
t is time, and
g is the acceleration due to gravity (equal to 9.8 m/s²)
(1) Dropped rock,
(3 x 10² m ) = 0(t) + 0.5(9.8 m/s²)(t²)
The value of t from this equation is 24.73 s
(2) Thrown rock with V₀ = 26 m/s
(3 x 10² m) = (26)(t) + 0.5(9.8 m/s²)(t²)
The value of t from the equation is 5.61 s
The difference between the tim,
difference = 24.73 s - 5.61 s
difference = 19.12 s
<em>ANSWER: 19.12 s</em>
Answer:
The distance between two objects
Explanation:
Depending on how far away or how close two objects are will affect the gravity.
Answer:
ΔL = 1.2 10⁻³ m
Explanation:
The expression for thermal expansion is
ΔL = α L₀ ΔT
in this case it indicates that the length is L₀ = 5 m for T₀ = 20C the final temperature is T_f = 40 C
the table shows the value of thermal expansion for steel α = 12 10⁻⁶ C⁻¹
let's calculate
ΔL = 12 10⁻⁶ 5 (40 -20)
ΔL = 1.2 10⁻³ m