Physical Science
posted by Audriana .
HELP WITH THESE PLEASE!
If you ride your bike at an average speed of 4km/h and nee to travel a total distance of 28 km, how long will it take you to reach your destination?
A small dog is trained to jump straight up a distance of 1.2 m. How much kinetic energy does the 7.2kg dog need to jump this high? ( the acceleration due to gravity is 9.8 m/s^2
As 390 g of hot milk cools in a mug, it transfers 30,000 J of heat to the environment. What is the temperature change of the milk? The specific heat of the milk is 3.9 J/g*C.
I Need to Be able to show all my work

1)
t=s/v= 28/4 = 7 hr
2)
KE=PE=mgh =7.2 •9.8•1.2 = …J
3)
Q=mcΔT
ΔT= Q/mc = 30000/0.39•3.9 = …