Answer:
the correct one is D
Explanation:
A question that can be answered with a scientific investigation must be a question where measurements of some kind can be made and with these measurements check that the question is correct or not.
When examining the answers the correct one is D
Answer:
0.68 seconds
Explanation:
Data provided in the question:
Mass of the box = 50 kg
Speed of the box = 1.0 m/s
Coefficient of friction, μ = 0.15
Now,
Force applied = μmg
Here,
g is the acceleration due to gravity = 9.8 m/s²
Thus,
F = 0.15 × 50 × 9.8
= 73.5 N
Also,
Force = Mass × Acceleration
thus,
73.5 N = 50 × a
or
a = 1.47 m/s²
After doubling the speed
Final speed = 2 × Initial speed
= 2 × 1 m/s
= 2 m/s
Also,
Acceleration = [change in speed] ÷ Time
or
1.47 = [ 2 - 1 ] ÷ Time
or
Time = 1 ÷ 1.47
or
Time = 0.68 seconds
One radian per second is equal to 206265 seconds of arc. (On a plane angle)
Answer: not be able to stop in time to miss the object
Explanation:
The phrase "Over-driving your headlights" means that a person is driving at such a speed that the vehicle's stopping distance is greater than the maximum viewable distance with the headlights on.
When this occurs, it will be impossible for the vehicle to stop moving in time to avoid an object viewed by the driver in the range of his headlights.
This is a <u>dangerous driving practice</u> and can be avoided by driving at <u>reduced speeds</u>.