Answer:
It's proved below
Step-by-step explanation:
We are given;
- K is the midpoint of JL
- M is the midpoint of LN
By definition of mid points, we can say that;
JK = KL and LM = MN
Now, we are given that JK = MN.
Thus, by substitution, we can deduce that; KL = LM
Thus is because JK can be replaced with KL and MN can be replaced with LM.
Thus, it is proved that KL = LM
Answer:
v_top = 2400 mi/hr
v_w = 400 mi/h
Step-by-step explanation:
Given:
- Total distance D = 4800 mi
- Headwind journey time taken t_up= 3 hr
- Tailwind journey time taken t_down = 2 hr
Find:
Find the top speed of Luke's snow speeder and the speed of the wind.
Solution:
- The speed of Luke v_l is in stationary frame is given by:
v_l = v_w + v_l/w
Where,
v_w: Wind speed
v_l/w: Luke speed relative to wind.
- The top speed is attained on his returned journey with tail wind. We will use distance time relationship to calculate as follows:
v_top = D / t_down
v_top = 4800 / 2
v_top = v_down = 2400 mi/hr
- Similarly his speed on his journey up with head wind was v_up:
v_up = D / t_up
v_up = 4800 / 3
v_up = 1600 mi/hr
- Now use the frame relations to find the wind speed v_w:
v_down = v_w + v_l/w
v_up = -v_w + v_l/w
- Solve equations simultaneously:
2400 = v_w + v_l/w
1600 = -v_w + v_l/w
4000 = 2*v_l/w
v_l/w = 2000 mi/h
v_w = 400 mi/h
Answer:
B
Step-by-step explanation
Car A started 10 miles east of Johnstown based on the fact he traveled 90 miles in 2 hours but was 100 away from Johnstown
Car B started 20 miles away, so that mean Car B was 10 more miles east than Car A when they started.
i think the median of the distribution is c