New evidence may support the theory -> then nothing
New evidence conflicts with the theory => rework theory / create a new one
Answer:
decrease
Explanation:
Addition of a lubricant such as oil to a surface will decrease friction. This makes the surface more greasy or slippery. This is very much efficient in machines, for example.
Answer:
14 m/s
Explanation:
The following data were obtained from the question:
Mass = 50 kg
Initial velocity (u) = 0 m/s
Height (h) = 10 m
Acceleration due to gravity (g) = 9.8 m/s²
Final velocity (v) =?
The velocity (v) with which the person hit the water can be obtained as shown below:
v² = u² + 2gh
v² = 0² + (2 × 9.8 × 10)
v² = 0 + 196
v² = 196
Take the square root of both side
v = √196
v = 14 m/s
Therefore, he will hit the water with a speed of 14 m/s
Answer:
D. 30m/s
Explanation:
According to the equation of motion
v=u +at
v = Final velocity
u = initial velocity
a = acceleration
t = time taken
Since we don't know the acceleration of the body, we will find its acceleration using newtons first law of motion F = ma
10000 =2000a
a = 5m/s²
initial velocity = 0m/s since the body starts from rest
v is what we are looking for
t = 6seconds
Substituting this datas in the formula
v = 0+ 5(6)
v = 30m/s (D)
