here's your correct answer.. please copy it..
Answer:
A) 50 seconds
B) 200 m
Explanation:
They are 500 metres apart.
And one of the bike loves at 6 m/s while the other loves at 4 m/s.
A) Let distance of the 6 m/s bike before they meet be x.
Thus, time = x/6
Since time = distance/speed
For the second bike at 4 m/s, his distance covered before they meet will be 500 - x
Thus, time = (500 - x)/4
Now they will meet each other at the same time. Thus;
x/6 = (500 - x)/4
Cross multiply to get;
4x = 3000 - 6x
6x + 4x = 3000
10x = 3000
x = 3000/10
x = 300 m
Thus, time will be;
t = 300/6
t = 50 seconds
B) Distance covered by the slower bike is (500 - x)
Since from a above, x = 300
Thus; distance = 500 - 300 = 200 m
-- Gravity adds 9.8 m/s to the downward speed of any object, every second ... as long as there are no other forces messing with it.
-- In 0.6 sec, gravity added (0.6x9.8)= 5.88 m/s to the downward speed of this ball.
-- This ball didn't start from zero. You threw it down with an initial speed of 1 m/s. So after 0.6 sec, with the help of gravity, its speed is
(1) + (5.88) = 6.88 m/s .
Pick choice-C .
Notice that we don't care how high it was off the ground when you threw it, just as long as it was high enough to keep falling for 0.6 sec without hitting the ground.
Answer:
Explanation:
In an elliptical orbit , the angular momentum of the planet remains constant because velocity of planet makes a right angle to the direction to the star .
mvr = constant .
mv₁r₁ = mv₂r₂
v₁r₁ = v₂r₂
v₁ x 21 = 38 x 75
v₁ = 135.71 km/s .
