Answer:
1. 19.28 secs
2. 154.22 m
Explanation:
The following data were obtained from the question:
Initial velocity (u) = 16 m/s
Final velocity (v) = 0
Force (F) = 1000 N
Mass (m) = 1200 Kg
Time (t) =..?
Distance (s) =...?
Next, we shall determine the acceleration of the car. This can be obtained as follow:
Force (F) = 1000 N
Mass (m) = 1200 Kg
Acceleration (a) =.?
Force (F) = mass (m) x acceleration (a)
F = ma
1000 = 1200 x a
Divide both side by 1200
a = 1000/1200
a = 0.83 m/s²
Since the car is coming to rest, it means it is decelerating. Therefore, the acceleration is – 0.83 m/s²
1. Determination of time taken for the car to halt i.e stop. This can be obtained as follow:
Initial velocity (u) = 16 m/s
Final velocity (v) = 0
acceleration (a) = – 0.83 m/s²
Time (t) =.?
v = u + at
0 = 16 + (–0.83 x t)
0 = 16 – 0.83t
Rearrange
0.83t = 16
Divide both side by 0.83
t = 16/0.83
t = 19.28 secs.
Therefore, the time taken for the car to halt is 19.28 secs.
2. Determination of the distance travelled by the car before coming to rest. This can be obtained as follow:
Initial velocity (u) = 16 m/s
Final velocity (v) = 0
acceleration (a) = – 0.83 m/s²
Distance (s) =..?
v² = u² + 2as
0 = 16² + (2 x –0.83 x s)
0 = 256 – 1.66s
Rearrange
1.66s = 256
Divide both side by 1.66
s = 256/1.66
s = 154.22 m
Therefore, the distance travelled by the car before coming to rest is 154.22 m.
Answer:
Uk = 44.145 J
Explanation:
To calculate the kinetic energie (Uk), you can make use of this formula:
Uk = m * g * h
given m = 0.500 kg g = 9.81 m/ s² and height is 9.00 m
Substituting in the formula gives:
Uk = 0.500 * 9.81 * 9.00
Uk = 44.145 J
Extra:
Now let's examine the formula in relation to the SI units. If you understand the following, it will give you great insight in how smart Phisics is inter twained by looking at formulas and their standard units. It will save you time in future to convert formulas, if you use the right standard units.
The formula for kinetic energie is:
Uk = m * g * h
given m in kg g in m/ s² and h in m.
From the formula, you see that the unit of Uk must be kg * m/s² * m which is kg* m²/s² and since Uk is normally given in J, these both forms must be the same !
The main unit for Uk is the Joule. Now <em>please see the picture</em>, which shows the relation between the J and other SI units. Please understand that you can construct your 'own' formulas based these units. Now here is the time saver:
Because almost always the right units are given in a question, or because sometimes you can look up a constant in a table with an exotic and seemingly complicated unit, but that says a lot about the formula which must have been some how involved!
By this, I hope you now understand the implication of using the right standard SI units and how that can help you figure out what formula is needed.
<span>Acceleration is a change in motion ... slowing down, speeding up,
or changing direction even if speed doesn't change</span>.
Answer:
D strengths and weakneses
Explanation:
Vector A is of magnitude 12 m and it makes an angle of 37 degree with Y axis
So here we can say that
Similarly we have
So here we have
option A is correct