Question

Riding his bike, dewayne can start from rest and get going at 12m/s in 4 seconds. Beth can get going 16m/s in 5 seconds. Who has a greater acceleration? How do you know?

Answer 1

Answer: The acceleration of Beth is more than the acceleration of Dewayne.

Explanation:

Acceleration is defined as the rate of change of velocity with respect to time.

Mathematically,

$a=\frac{v-u}{t}$

where,

v = final velocity

u = initial velocity

t = time taken

• For Dewayne:

We are given:

$v=12m/s\\u=0m/s\\t=4sec$

Putting values in above equation, we get:

$a=\frac{12-0}{4}=3m/s^2$

Acceleration of Dewayne = $3m/s^2$

• For Beth:

We are given:

$v=16m/s\\u=0m/s\\t=5sec$

Putting values in above equation, we get:

$a=\frac{16-0}{5}=3.2m/s^2$

Acceleration of Beth = $3.2m/s^2$

Hence, the acceleration of Beth is more than the acceleration of Dewayne.

Answer 2

Answer: Beth

Explanation: Dewayne (a) = 12/4 = 3m/s^2.

Beth (a) = 16/5 = 3.2 m/s^2.

So, Beth is the answer.