Question

David's new bike can accelerate from rest to 45.0 m/s in just 6.00 s. the combined mass of david and his bike is 225.43 kg. what is the magnitude of the net (unbalanced) force that can cause the acceleration?

Answer 1

Answer: The magnitude of the net (unbalanced) force that can cause the acceleration is 1690.725 N.

Explanation:

Acceleration of the bike =[tex[\frac{velocity}{time}=\frac{45m/s}{6.00 s}=7.5 m/s^2[/tex]

Mass of the David and his bike together =  225.43 kg

Magnitude of the force that can cause the acceleration:

$Force=Mass\times Acceleration=225.43 kg\times 7.5 m/s^2=1690.725 N$

The magnitude of the net (unbalanced) force that can cause the acceleration is 1690.725 N.

Answer 2

As we know that acceleration is given as

$a = \frac{v_f - v_i}{t}$

here we know that

$v_f = 45 m/s$

$v_i = 0$

$t = 6s$

now we will have

$a = \frac{45- 0}{6} = 7.5 m/s^2$

now as per Newton's II law we can say

$F = ma$

$F = 225.43 \times 7.5$

$F = 1690.725 N$