Answer:
6 s
Explanation:
First of all, we calculate the acceleration of the car in the initial situation, using the equation
where
v = 30 is the final velocity of the car
u = 0 is the initial velocity
t = 12 s is the time taken
Substituting,
So, this is the acceleration of the car.
In the second situation, the car velocity goes from
u = 0
to
v = 15 m/s
So, we can use again the same equation to find t, the time it takes for the velocity of the car to change between these values:
Answer:
tension in rope = 25.0 N
Explanation:
- Two forces act on the suspended weight. The force coming down is the gravitational force and the upward force by the tension in the rope.
- Since the suspended weight is not accelerating so that the net force will be zero. Therefore the tension in the rope should be 25 N.
∑F = F - W = 0
so
F = W
so tension in rope = F = T = 25 N
Answer:
A = B = C > D
Explanation:
Work done to stop the disc is given as
so we have
(a) –2 rad/s, 5 rad/s;
(b) 2 rad/s, 5 rad/s;
(c) –2 rad/s, –5 rad/s; and
(d) 2 rad/s, –5 rad/s.
So we have
so we have
A = B = C > D
Answer:
Air slows down The fall of any object including a ball.