Question

acceleration bell work - student edition
data below shows the winners of different races for school athletics. however, some variables have gone missing.
complete the table below using the equation v = d/t:
d = vt
event\tdistance(m)\ttime(s)\tspeed (m/s)
junior girls sprint\t100\t14.4\t6.9
junior boys sprint\t100\t13.2
senior girls sprint\t200\t\t6.0
senior boys sprint\t\t32.4\t6.2
800m girls run\t800\t142.2
800m boys run\t800\t145.4
1500m girls run\t1500\t\t4.7
1500m boys run\t1500\t302.4
relay\t400\t\t6.5
relay\t\t63.2\t6.3

Explanation:

Step1: Recall the speed - distance - time formula

The formula is $v=\frac{d}{t}$, where $v$ is speed, $d$ is distance and $t$ is time. We can also use it in the forms $d = vt$ and $t=\frac{d}{v}$ to find the missing values in the table.

Step2: Calculate the speed for junior boys sprint

Given $d = 100$m and $t=13.2$s, using $v=\frac{d}{t}$, we have $v=\frac{100}{13.2}\approx7.58$ m/s.

Step3: Calculate the time for senior girls sprint

Given $d = 200$m and $v = 6.0$m/s, using $t=\frac{d}{v}$, we get $t=\frac{200}{6.0}\approx33.33$s.

Step4: Calculate the distance for senior boys sprint

Given $t = 32.4$s and $v = 6.2$m/s, using $d=vt$, we obtain $d=6.2\times32.4 = 200.88$m.

Step5: Calculate the speed for 800m girls run

Given $d = 800$m and $t = 142.2$s, using $v=\frac{d}{t}$, we have $v=\frac{800}{142.2}\approx5.63$ m/s.

Step6: Calculate the speed for 800m boys run

Given $d = 800$m and $t = 145.4$s, using $v=\frac{d}{t}$, we get $v=\frac{800}{145.4}\approx5.50$ m/s.

Step7: Calculate the time for 1500m girls run

Given $d = 1500$m and $v = 4.7$m/s, using $t=\frac{d}{v}$, we obtain $t=\frac{1500}{4.7}\approx319.15$s.

Step8: Calculate the distance for 1500m boys run

Given $t = 302.4$s and $v = 4.7$m/s, using $d=vt$, we have $d=4.7\times302.4 = 1421.28$m.

Step9: Calculate the time for 400m relay

Given $d = 400$m and $v = 6.5$m/s, using $t=\frac{d}{v}$, we get $t=\frac{400}{6.5}\approx61.54$s.

Step10: Calculate the distance for 400m relay

Given $t = 63.2$s and $v = 6.3$m/s, using $d=vt$, we obtain $d=6.3\times63.2 = 398.16$m.

Answer:

Event	Distance(m)	Time(s)	Speed (m/s)
Junior boys sprint	100	13.2	7.58
Senior girls sprint	200	33.33	6.0
Senior boys sprint	200.88	32.4	6.2
800m girls run	800	142.2	5.63
800m boys run	800	145.4	5.50
1500m girls run	1500	319.15	4.7
1500m boys run	1421.28	302.4	4.7
400m relay	400	61.54	6.5
400m relay	398.16	63.2	6.3