Question

Question No. 11. What is the acceleration of a car that goes from 20 Km/hr to 100 Km/hr in 8 seconds?2. A plane goes from 500 Km/hr to 1,400 Km/hr in 3 minutes. What is its acceleration?3. A car going at 80 mph comes to a complete stop in 6 seconds. Calculate the acceleration4. A train accelerates at a rate of 2 Km/hr/sec for a period of 30 seconds. If its initial speed was 15 Km/hr,what will be its final speed?5. If an object at rest accelerates by 5 meters/sec/sec, what will be its speed after 15 seconds?6. How long will it take for a car to come to a complete stop when traveling at 45 miles per hour if itsacceleration is -3 miles/hr/sec?7. A car going at 75 miles/hr slows down to 25 miles/hr in 2.5 sec; calculate the acceleration.8. What was the initial speed of a truck that ended up with a speed of 65 Km/hr after it accelerated3 Km/hr/sec for a period of 5 seconds?9. If a baseball lands with a speed of 80 miles/hr after traveling with an acceleration of -6 miles/hr/sec for 5 seconds, what was the initial speed at which the ball was hit?10. What distance will a bicyclist cover in 25 seconds if he pedals with an acceleration of 2.5 meters/sec/sec?11. What was the acceleration of a runner that ran a distance of 200 meters in 17 seconds?12. How long will it take for a car accelerating at 4 meters/sec/sec to cover a distance of 500 meters?

Answer 1

Given:

The initial velocity of the car is

`\begin{gathered} v_i=20\text{ km/hr} \\ =20*\frac{1000\text{ m}}{3600\text{ s}} \\ =5.556\text{ m/s} \end{gathered}`

The final velocity of the car is

`\begin{gathered} v_f=100\text{ km/hr} \\ =\text{ 100}*(5)/(18) \\ =\text{ 27.778 m/s} \end{gathered}`

The time duration is t = 8 s

To find the acceleration of a car.

Step-by-step explanation:

The acceleration of the car will be

`\begin{gathered} a=(v_f-v_i)/(t) \\ =(27.778-5.556)/(8) \\ =2.775\text{ m/s}^2 \end{gathered}`

Thus, the acceleration of the car is 2.775 m/s.