Answer:
If an object is moving with a constant velocity, then by definition it has zero acceleration. So there is no net force acting on the object. The total work done on the object is thus 0 (that's not to say that there isn't work done by individual forces on the object, but the sum is 0 ).
Explanation:
In the middle, when the object was changing position at a constant velocity, the acceleration was 0. This is because the object is no longer changing its velocity and is moving at a constant rate.
Answer:
Explanation:
volume of water being lifted
= π r² h , where r is radius of cylinder and h is height of cylinder
= 3.14 x5² x 10
= 785 m³
mass of water = 785 x 10³ kg
mass of this much of water is lifted so that its centre of mass is lifted by height
10 / 2 = 5m .
So work done = mgh , m is mass of water , h is displacement of centre of mass and g is acceleration due to gravity
= 785 x 10³ x 9.8 x 5
= 38.465 x 10⁶ J
Vo = 5.89 m/s Y = 1.27 m g = 9.81 m/s^2
Time to height
Tr = Vo / g Tr = (5.89 m/s) / (9.81 m/s^2) Tr = 0.60 s
Max height achieved is:
H = Vo^2 / [2g] H = (5.89 )^2 / [ 2 * (9.81) ] H = (34.69) / [19.62] H = 1.77 m
It falls that distance, minus Andrew's catch distance:
h = H - Y h = (1.77 m) - (1.27 m) h = 0.5 m
Time to descend is therefore:
Tf = √ { [2h] / g ] Tf = √ { [ 2 * (0.5 m) ] / (9.81 m/s^2) } Tf = √ { [ 1.0 m ] / (9.81 m/s^2) } Tf = √ { 0.102 s^2 } Tf = 0.32 s
Total time is rise plus fall therefore:
Tt = Tr + Tf Tt = (0.60 s) + (0.32 s) Tt = 0.92 s (ANSWER)
Answer:
Derived in explanation
Explanation:
The law of universal gravitation was discovered by Newton in 1686. According to this law:
“Every object in this universe attracts other body with a force, which is directly proportional to the product of their masses and inversely proportional to the square of the distance between their centers.”
Consider two bodies ‘A’ and ‘B’ having masses ‘m1’ and ‘m2’, respectively. They are placed with their centers at distance ‘r’ from each other.
According to this law, force is directly proportional to the product of their masses, that is:
Also, the force is inversely proportional to the square of the distance between them, that is:
On combining both equations we get:
Where ‘G’ is called ‘Gravitational Constant’ and its value is 6.67 x 10⁻¹¹ Nm²/kg².
Answer:
0.912
Explanation:
Given that
Height of bouncing of the ball, h = 1.71 m
Number of times the ball bounced, n = 4 times
Height from which the ball was dropped, H = 2.47
First, let's start by defining what coefficient of restitution means
Coefficient of Restitution, CoR is the "ratio of the final to initial relative velocity between two objects after they collide. It normally ranges from 0 to 1 where 1 would be a perfectly elastic collision."
It is mathematically represented as
CoR = (velocity after collision) / (velocity before collision)
1.71 = 2.47 * c^4, where c = CoR
1.71/2.47 = c^4
c^4 = 0.6923
c = 4th root of 0.6923
c = 0.912
