Question

1. nascar fans love race day when they get a chance to cheer on their favorite team! a driver was able to travel 600.0 miles in 4.0 hours, what was his average speed?

1. a parachute on a racing dragster opens and changes the speed of the car from 85 m/s to 40 m/s in a period of 4.5 seconds. what is the acceleration of the dragster?

Explanation:

Problem 1

Step1: Recall speed formula

The formula for average speed \( v \) is \( v=\frac{d}{t} \), where \( d \) is distance and \( t \) is time.

Step2: Substitute values

Given \( d = 600.0 \) miles and \( t = 4.0 \) hours. Substitute into the formula: \( v=\frac{600.0}{4.0} \).

Step3: Calculate the result

\( \frac{600.0}{4.0}=150 \) miles per hour.

Step1: Recall acceleration formula

The formula for acceleration \( a \) is \( a=\frac{v_f - v_i}{t} \), where \( v_f \) is final velocity, \( v_i \) is initial velocity, and \( t \) is time.

Step2: Identify values

\( v_i = 85 \) m/s, \( v_f = 40 \) m/s, \( t = 4.5 \) s.

Step3: Substitute and calculate

\( a=\frac{40 - 85}{4.5}=\frac{- 45}{4.5}=- 10 \) m/s². The negative sign indicates deceleration.

Answer:

150 miles per hour

Problem 2