Negative acceleration, faster car?
"Negative acceleration, faster car?" is a free, interactive Class 11 Physics simulation for NEET and JEE, built on the lesson "Acceleration" in Motion in a Straight Line. Here v₀ = +6 m/s and a = −2 m/s². Press Play and watch the label on the track and the speed–time graph. Green stretches are speeding up, red ones slowing down. The sign of a alone says nothing about speeding up. Compare it with the sign of v: same sign, the body speeds up; opposite signs, it slows down. JEE Main asked 30 questions from this chapter across the 42 shifts Lumi has analysed (2017–2026).
From the lesson Acceleration in Motion in a Straight Line. Change the values and watch what happens.
In JEE Main
42 shifts analysed
30 questions from Motion in a Straight Line across the 42 JEE Main shifts Lumi has analysed (2017–2026).
The idea behind it
NCERT § "Acceleration"
- Dividing the change in velocity by the time interval gives the average acceleration; the instantaneous acceleration is a = dv/dt = d²x/dt².
- Acceleration is the slope of the velocity-time (v-t) graph at a given instant; SI unit m s⁻².
- The sign of acceleration is fixed by the chosen positive direction. A body speeds up when v and a have the same sign and slows down when they have opposite signs.
- A body can have zero velocity and non-zero acceleration at the same instant, for example at the highest point of a vertical throw.
- With uniform (constant) acceleration, plotting v against t gives a straight line; for uniform motion (a = 0) that line runs parallel to the time axis.
- The x-t graph curves upward when a > 0 and downward when a < 0; for a = 0 it is a straight line.
- The area under the v-t graph over an interval equals the displacement in that interval, with area below the time axis counted as negative.
Questions
3 answers
- What does the "Negative acceleration, faster car?" simulation show?
- Here v₀ = +6 m/s and a = −2 m/s². Press Play and watch the label on the track and the speed–time graph. Green stretches are speeding up, red ones slowing down.
- Does JEE Main ask questions from Motion in a Straight Line?
- Yes. JEE Main asked 30 questions from this chapter across the 42 shifts Lumi has analysed (2017–2026).
- Is this simulation free?
- Yes. It is free and runs in the browser on a phone or a laptop. It belongs to the lesson "Acceleration" in Motion in a Straight Line (Class 11 Physics).
Embed this simulation
Free, with a link back
Teaching this idea? Put the simulation on your own page or LMS with this code.