Answer:
Explanation:
Given
Distance to grandmother's house=100 mi
it is given that during return trip Julie spend equal time driving with speed 30 mph and 70 mph
Let Julie travel x mi with 30 mph and 100-x with 70 mph
x=30 mi
Therefore
Julie's Average speed on the way to Grandmother's house
=42 mph
On return trip
Answer:
0.143 m
Explanation:
The relationship between force applied on a string and stretching of the spring is given by Hooke's law:
where
F is the force exerted on the spring
k is the spring constant of the spring
x is the stretching of the spring from its equilibrium position
In this problem, we have:
F = 20 N is the force applied on the spring
k = 140 N/m is the spring constant
Solving for x, we find how far the spring will stretch: