Answer:
40sec
Explanation:
Data
Work = 440 J
Power= 11watt
time = ?
Power = work done/time
===> time = work done/power
= 440/11
= 40sec
Answer:
Explanation:
Let h be the height .
initial velocity in first case u = 0
final velocity v = 6 m /s
acceleration due to gravity g = 9.8 m /s²
v² = u² + 2 g h
6² = 0 + 2 x 9.8 x h
h = 1.837 m .
For second case u = 3 m /s
v² = u² + 2 gh
= 3² + 2 x 1.837 x 9.8
= 9 + 36
= 45 m
v = 6.7 m /s
Here we can say that there is no external torque on this system
So here we can say that angular momentum is conserved
so here we will have

now we have



similarly let the final distance is "r"
so now we have


now from above equation we have


so final distance is 0.04 m between them
Answer:
R=3818Km
Explanation:
Take a look at the picture. Point A is when you start the stopwatch. Then you stand, the planet rotates an angle α and you are standing at point B.
Since you travel 2π radians in 24H, the angle can be calculated as:
t being expressed in hours.

From the triangle formed by A,B and the center of the planet, we know that:
Solving for r, we get:

Given the velocity-time graph of an object.
The slope of a velocity-time graph gives the acceleration acting on the object.
From the graph, we can see that the slope of the graph is zero. That is, the velocity of the object is constant and hence the net acceleration acting on the object is zero.
From Newton's second law, the net force acting on an object is given by the product of the mass of the object and its velocity. Therefore when the acceleration of the object is zero, the net force on the object is also zero.
Therefore the net force acting on the given object is zero. Hence, the correct answer is option A.