Answer:
V1 = 60 km/h
V2 = 40 Km/h
Step-by-step explanation:
The speed of an object is defined as
Speed = distance / time
Let
V1 be the speed of the faster car
V2 be the speed of the other car
t1 the time it took for the first car to arrive
t2 the time it took for the second car to arrive
d1 the distance traveled by first car
d2 the distance traveled by second car
We know thanks to the problem that
V1 = V2 + 20 Km/h
t1 = t2 - 1 hour
d1 = d2 = 120 Km
d1 = V1 * t1
d2 = V2* t2
V1 * t1 = V2* t2
V1* t1 = (V1 -20)*(t1 +1)
The system of equations
(V1 -20)*(t1 +1) = 120
V1 * t1 = 120
120 + (120/t1) -20*t1 = 140
(120/t1) -20*t1 = 20
Which gives,
t1 = 2
This means
V1 = 60 km/h
V2 = V1 - 20 Km/h = 40 Km/h
Answer:
2.17ft/s
Step-by-step explanation:
Look at the sketch of ladder at the beginning and after 3 seconds it starts to fall,
Distance of ladder from the wall 3 seconds after ladder starts to fall = Initial distance+ Velocity× time
= 6 + 2×3
= 12ft
Use trignometry to find out the speed of the top of ladder
cosθ= 12/20
θ= 0.825 rad
tan θ= v/2
v= 2.17ft/s
Cot^2x - cot^2x cos^2x
= cot^2x - {(cot^2x)(cos^2x)}
= cot^2x { 1 - cos^2x }
= cot^2x { sin^2x }
= (cos^2x/sin^2x) { sin^2x }
= cos^2x
Answer:
7.8 and 18.8 is your answer
Step-by-step explanation:
Answer:
20 hours.
Step-by-step explanation.
The total distance traveled was 400 miles. Then I divided 400 by 20. I got 20.
