- #1
STM
- 7
- 0
- Homework Statement
- Hi I am completely stuck on this part of my work, I’ve got the time graph started but am unsure what equations and how to work it out can some please help
- Relevant Equations
- V=U+AT
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So first, tell me what you understand bySTM said:I am totally lost on this assignment as I missed a few weeks at college for personal reasons and I am really lost on this one as I didn’t cover these topics
Merlin3189 said:So velocity is how much distance you travel per unit of time, ##v=\frac {distance \, travelled}{time \, taken}##
Acceleration is how much the velocity changes per unit of time, ##a=\frac {change\, of\, velocity}{time\, taken}##
Using that relationship;
For part (i), you know; the time taken, the velocity at the start, the velocity at the end, so you can calculate the change in velocity in the given time and then the acceleration.
For (ii) you know the acceleration, you know the velocity at the start and at the end, so you can calculate the change in velocity and the time it took.
Merlin3189 said:(i) & (ii) fine.
For (iii) you need to tackle it in three sections. The formulae you are using apply to constant acceleration. But the acceleration is different in each phase.
Now, I don't know what the expressionyou quote here is supposed to do.
##\frac 1 2 a t## would give you half the change in speed over time t with acceleration a
You need to find distance.
You know all the speeds and times, so that is the sort of formula you want:
distance = function of (speeds , time)
For constant speed, distance = speed x time
But when speed is changing linearly (which is what happens when acceleration is constant) you can say
distance = (average speed) x time
I think you also need to learn (and understand) what are known as the SUVAT equations.
STM said:On part b, I think I have the formula correct, but am I little in sure on the correct figures to put in
Edit ( does this look correct)
View attachment 258469
Merlin3189 said:Yes . These answers are all near enough right.
Thank youMerlin3189 said:You should note two points:
When you work out an early result, like the acceleration, you should record it to more significant figures and use that value in later calculations. If you use rounded off values in later calculations, the rounding may get multiplied and cause significant error.
Units for acceleration are metres per (second squared) ## \frac {m}{s^2} \, \text{ or } \, m/s^2##
not m/s which is speed or velocity.
Vehicle acceleration is the rate at which the velocity of a vehicle changes over time. It is typically measured in meters per second squared (m/s^2).
Acceleration can be calculated by dividing the change in velocity by the change in time. The formula for acceleration is a = (vf - vi)/t, where a is acceleration, vf is final velocity, vi is initial velocity, and t is time.
Linear acceleration refers to the change in velocity in a straight line, while angular acceleration refers to the change in rotational velocity. Linear acceleration is typically measured in m/s^2, while angular acceleration is measured in radians per second squared (rad/s^2).
According to Newton's Second Law of Motion, the acceleration of an object is directly proportional to the net force acting on it and inversely proportional to its mass. This means that a heavier vehicle will require more force to accelerate at the same rate as a lighter vehicle.
Other factors that can affect vehicle acceleration include friction, air resistance, and the condition of the vehicle's engine and tires. These can impact the amount of force required to accelerate the vehicle and can ultimately affect its acceleration rate.