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5answers
934 views

What is the difference between uniform velocity and constant velocity?

I think that uniform velocity implies constant speed but not constant direction. while constant velocity implies constant speed without any changes in direction. Both tell us that there's no ...
4answers
93 views

Problem on circular motion

If a body moves such that its net acceleration always points towards a particular point does this body have constant angular velocity around this point?
0answers
87 views

Angle between velocity and acceleration vector, and interpretation of pathway [closed]

I just started studying mechanics, and I am stuck with the following question: $$\vec{r}(t)=a \sin(\alpha t^2)\hat{x}+b \cos(\alpha t^2)\hat{y}$$ I was asked to find the formula that expresses the ...
2answers
85 views

How can I understand if an object stay (zero velocity) or moving with constant velocity (zero acceleration)

I thought a scenario like; lets say I am looking an object and there is nothing except this object. Is there a way to understand that if this object is stay on its position or if object moving with a ...
5answers
68 views

Equation of distance and time

How is this equation derived? $$r = r_0 + ut + at²/2$$ where $r_0$ is the initial position of particle and $r$ is the position of the particle after all the motion it has undergone, $a$ and $t$ ...
9answers
6k views

The instant an accelerating object has zero speed, is it speeding up, slowing down, or neither?

This problem is from Khan Academy. Specifically for the blue point circled in red, the answer is that at this blue point, the object is neither speeding up nor slowing down. When I think about the ...
2answers
28 views

Intuition of Distance covered when accelerating [duplicate]

When you're moving at $5$ m/s for $1$ second, you have traveled $5$ m. When you're moving at $5$ m/s (initial velocity) and you accelerate $2$ m/s for $1$ second, you have traveled $5$ m + $1$ m (...
1answer
60 views

Use of direction of downward velocity in equation of motion

[NOTE: I am not asking anyone to solve the question below but to point out where I might be wrong] Q- A skier jumps from a horizontal track and lands on a steeper track with a launch angle of ∅=11.3°(...
2answers
147 views

2answers
706 views

The human body can survive an acceleration trauma incident (sudden stop) if the magnitude of the acceleration is less than [closed]

The human body can survive an acceleration trauma incident (sudden stop) if the magnitude of the acceleration is less than 250 m/s². If you are in an auto- mobile accident with an initial speed of 105 ...
1answer
75 views

How to Find Jerk from Discrete Velocity Data?

I have measured the velocity of an object at discrete intervals. I want to find the corresponding acceleration and jerk of the object. How do I do this with discrete values rather than continuous ...
2answers
139 views

What would the position vs. time graph look like if the velocity vs. time graph was a curve?

In my physics class we are learning about velocity vs. time graphs and position vs. time graphs for an object. We have learned that if the object is moving with constant velocity (this would be a ...
3answers
65 views

How to know which constant acceleration equation to use? [closed]

The question I'm working on: This is the answer: For (b), I just want to know why we use ((v+u)/2)t) to find the displacement of the mailbag. It is clearly a free falling object that has ...
1answer
18 views

Average Velocity Question (isolation?)

So there is this question i've been having trouble with for the past hour. It involved a child going down a ramp on a sled at and angle theta with a total system of mass. accelerates down a hill of ...
5answers
118 views

How to determine the direction of a vector?

I have been learning about vectors and acceleration recently and I still don't understand how to determine the direction of a vector. For instance, if we consider a freely falling particle and ...
5answers
46 views

Why do objects move back after collision?

When a ball collides with a wall, the ball moves in the opposite direction, why does this happen if Newton's third law operates. I mean the ball collided with the wall and imparted a force on it and ...
1answer
40 views

Acceleration in $x$ and $y$ directions of a pendulum swinging? [closed]

If there is a pendulum that gets released and only moves in two dimensions, what would it’s acceleration be in the x and y directions, meaning at what rate is the velocity changing in the x and y ...
14answers
20k views

Why doesn't a braking car move backwards?

The net force on an object is equal to the mass times the acceleration, $F = ma$ When I brake on a (moving) car, the net force is negative, therefore causing the resulting acceleration to also be ...
2answers
160 views

Does Euler number $e$ have a role in kinematics?

Euler number $e$ is often explained with the example of compound continuous interest. I was wondering if it could also be illustrated with an example about the displacement of a body (although not an ...
2answers
91 views

Confused with derivative and partial derivative

suppose $x=f(t)$ with a constant acceleration. Then does $\frac{\text d x}{\text d t} = \frac{\partial (x)}{\partial(t)}$ since the position in $x$ only changes with time? Then the acceleration in ...
1answer
42 views

Interpreting derivatives

So we have a function such that the distance moved by a particle (say $s$) is proportional to $sin(Ct)$ where $C$ is a constant. Now i needed to show that the rate of change of velocity is directly ...
2answers
51 views

Lateral acceleration to angle [closed]

I am doing a 2D simulation in discrete steps of a vehicle. The vehicle will desire a certain lateral acc. at any given timestep. So I would like to know the delta angle of the velocity vector after ...