Answer:
111.5 m
Explanation:
Given that You are driving to the grocery store at 14 m/s. You are 115 m from an intersection when the traffic light turns red. Assume that your reaction time is 0.50 s and that your car brakes with constant acceleration.
Use first equation of motion
V = U - at
Since the car is going to rest, V = 0 and a = negative
0 = 14 - a × 0.5
0.5a = 14
a = 14 /0.5
a = 28 m/s^2
Let us use second equation of motion
S = Ut - 1/2at^2
S = 14 × 0.5 - 0.5 × 28 × 0.5^2
S = 7 - 3.5
S = 3.5 m
115 - 3.5 = 111.5
Therefore, you are 111.5 metres from the intersection (in m) when you begin to apply the brakes.
Answer:
We live in a very adaptable environment. If we cannot adapt to the environment, we will not be able to survive.
Explanation:
The correct answer is b i believe
Answer:
(a) 1.16 s
(b)0.861 Hz
Explanation:
(a) Period : The period of a simple harmonic motion is the time in seconds, required for a object undergoing oscillation to complete one cycle.
From the question,
If 1550 cycles is completed in (30×60) seconds,
1 cycle is completed in x seconds
x = 30×60/1550
x = 1.16 s
Hence the period is 1.16 seconds.
(b) Frequency : This can be defined as the number of cycles that is completed in one seconds, by an oscillating body. The S.I unit of frequency is Hertz (Hz).
Mathematically, Frequency is given as
F = 1/T ........................... Equation 1
Where F = frequency, T = period.
Given: T = 1.16 s.
Substitute into equation 1
F = 1/1.16
F = 0.862 Hz
Hence thee frequency = 0.862 Hz
Matter either loses or absorbs energy when it changes from one state to another. For example, when matter changes from a liquid to a solid, it loses energy. The opposite happens when matter changes from a solid to a liquid. For a solid to change to a liquid, matter must absorb energy from its surroundings.
