Question

A car starts from rest & acquire a velocity of 54km/h in 2 sec. Find-

Answer 1

Answer:

a. Acceleration, a = 7.5 m/s

b. Distance, S = 15 meters

c. Force = 7500 Newton

Explanation:

Given the following data;

Mass = 1000 kg

Initial velocity = 0 m/s (since it's starting from rest).

Final velocity = 54 km/h

Time = 2 secs

Conversion:

54 km/h to m/s = 54*1000/3600 = 15 m/s

a. To find the following acceleration;

Mathematically, acceleration is given by the equation;

$Acceleration (a) = \frac{initial speed - final speed}{time}$

Substituting into the formula, we have;

$Acceleration = \frac{15 - 0}{2}$

$Acceleration = \frac{15}{2}$

Acceleration, a = 7.5 m/s

b. To find the distance, we would use the second equation of motion.

$S = ut + \frac {1}{2}at^{2}$

Where;

• S represents the displacement or height measured in meters.
• u represents the initial velocity measured in meters per seconds.
• t represents the time measured in seconds.
• a represents acceleration measured in meters per seconds square.

Substituting into the equation, we have;

$S = 0*2 + \frac {1}{2}*(7.5)*2^{2}$

$S = 0 + 3.75*4$

$S = 15$

Distance, S = 15 meters

c. To find the force, we would use the following formula;

$Force = mass * acceleration$

$Force = 1000 * 7.5$

Force = 7500 Newton