Question
Find the average force needed to accelerate a car weighing 500kg from rest to 72km/h in a distance of 25m.
✓
Answer
m = 500kg, u = 0, v = 72km/h = 20m/s$\text{a}=\frac{\text{v}^2-\text{u}^2}{2\text{s}}$
$\Rightarrow\frac{400}{50}=8\text{m}/\text{sec}^2$
force needed to accelerate the car F = ma = 500 × 8 = 4000N
Need a full question paper?
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
Explore more
Similar questions
A particular guitar wire is 30.0cm long and vibrates at a frequency of 196Hz when no finger is placed on it. The next higher notes on the scale are 220Hz, 247Hz, 262Hz and 294Hz. How far from the end of the string must the finger be placed to play these notes?
A 1 meter thick cement wall can withstand a pressure of $10^5 N / m ^2$. What should be the thickness of the wall at the base of a 200 m depth water of dam?
(Density of water $=10^3 kg / m ^3$ and acceleration due to gravity $=9.8 m / s ^2$ )
→(Density of water $=10^3 kg / m ^3$ and acceleration due to gravity $=9.8 m / s ^2$ )
Explain why Water on a clean glass surface tends to spread out while mercury on the same surface tends to form drops. (Put differently, water wets glass while mercury does not.)
Look at the graphs carefully and state, with reasons, which of these cannot possibly represent one-dimensional motion of a particle.
A mass $M_1$ revolves around another mass $M_2$ in a path of radius r, what is the angular momentum associated with $M_1$?
→A simple pendulum makes 60 oscillations per minute. Find its effective length.
When two waves of almost equal frequencies $n_1$ and $n_2$ reach at a point simultaneously, what is the time interval between successive maxima?
→If $\vec{\text{A}}=(-2\hat{\text{i}}+3\hat{\text{j}}-4\hat{\text{k}})$ and $\vec{\text{B}}=(3\hat{\text{i}}-4\hat{\text{j}}+5\hat{\text{k}})$ find $\vec{\text{A}}\times\vec{\text{B}}$ and $\vec{\text{A}}.\vec{\text{B}}$
→Why rooms are provided with the ventilators near the roof?
Explain, what do you understand by the efficiency of a heat engine?