Average acceleration

Q. A car increases its speed from $20\text{km/h}$ to $30\text{km/h}$ in $1\text{s}$ then its acceleration is -

1. $2.78{\text{m/s}}^2$
2. $5{\text{m/s}}^2$
3. $7{\text{m/s}}^2$
4. $3.32{\text{m/s}}^2$

Q. When a car driver travelling at a speed of $20\text{m/s}$ applies the brakes and brings the car to rest in $4\text{sec}$, the acceleration of car will be :

1. $2{\text{m/s}}^2$
2. $3{\text{m/s}}^2$
3. $5{\text{m/s}}^2$
4. $-5{\text{m/s}}^2$

Q. A car increases its speed from $20\text{km/h}$ to $30\text{km/h}$ in $1\text{s}$ then its acceleration is -

1. $2.78{\text{m/s}}^2$
2. $5{\text{m/s}}^2$
3. $7{\text{m/s}}^2$
4. $3.32{\text{m/s}}^2$

Q. A train starts from rest and accelerate uniformly at the rate of $5{\text{m/s}}^2$ for $5\text{sec}$. Calculate the velocity of train in $5\text{sec}$.

1. $20\text{m/s}$
2. $25\text{m/s}$
3. $10\text{m/s}$
4. $5\text{m/s}$

Q.

A Porsche can go from $0\text{km/hr}$ to $100\text{km/hr}$ in $10\text{s}$. What is its average acceleration?

1. $2.77\text{m}/s^2$

2. $3.66\text{m}/s^2$

3. $-3.66\text{m}/s^2$

4. $0\text{m}/s^2$