Explanation:
Let the speeds of father and son are 
. The kinetic energies of father and son are 
. The mass of father and son are 
(a) According to given conditions, 
And 
Kinetic energy of father is given by :
.............(1)
Kinetic energy of son is given by :
...........(2)
From equation (1), (2) we get :
..............(3)
If the speed of father is speed up by 1.5 m/s, so the ratio of kinetic energies is given by :
Using equation (3) in above equation, we get :
(b) Put the value of 
in equation (3) as :
Hence, this is the required solution.
Answer:
All points to the left of zero are negative
Explanation:
Answer:
The lightbulb will NOT light.
Explanation:
You put me in a difficult position. I can't help it, but the "sample answer" is by far the best way to explain this, briefly and correctly. There's no other choice but to copy it.
This is a short circuit. The branch without the bulb has almost no resistance, so all the current will flow through that branch instead of flowing through the bulb.
<em>If</em> the lower switch were <u>opened</u>, THEN we would have a series circuit. Current would no longer have any other choice but to flow through the bulb, and the bulb would light.
Answer:
a) V_f = 25.514 m/s
b) Q =53.46 degrees CCW from + x-axis
Explanation:
Given:
- Initial speed V_i = 20.5 j m/s
- Acceleration a = 0.31 i m/s^2
- Time duration for acceleration t = 49.0 s
Find:
(a) What is the magnitude of the satellite's velocity when the thruster turns off?
(b) What is the direction of the satellite's velocity when the thruster turns off? Give your answer as an angle measured counterclockwise from the +x-axis.
Solution:
- We can apply the kinematic equation of motion for our problem assuming a constant acceleration as given:
V_f = V_i + a*t
V_f = 20.5 j + 0.31 i *49
V_f = 20.5 j + 15.19 i
- The magnitude of the velocity vector is given by:
V_f = sqrt ( 20.5^2 + 15.19^2)
V_f = sqrt(650.9861)
V_f = 25.514 m/s
- The direction of the velocity vector can be computed by using x and y components of velocity found above:
tan(Q) = (V_y / V_x)
Q = arctan (20.5 / 15.19)
Q =53.46 degrees
- The velocity vector is at angle @ 53.46 degrees CCW from the positive x-axis.
D. The red car is moving faster than the blue car
