Answer:
NO
Explanation:
No, a machine cannot be 100% efficient. This is due to the movement of the moving parts siding against each other and causing friction. This friction is the one that creates heat and causes wear and tear between moving ports f the machine hence making the machine to decrease in efficiency with time
The gravitational potential energy of the object is 100 J.
Gravitational potential energy stored in an object is the work done in raising the object to a height <em>h</em> against the gravitational force acting on it.
The gravitational force acting on a body is its weight mg, where m is its mass and g, the acceleration due to gravity.
Work done by a force is equal to the product of the force and the displacement made by the point of application of the force.
The weight of the object is given as 20 J and it is raised to a height of 5 m.
The gravitational potential energy of the object is 100 J.
Answer:
-24.28571 rad/s²
29.57239 revolutions
3.91176 seconds
52.026478 m
Explanation:
= Tangential acceleration = -6.8 m/s²
r = Radius of wheel = 0.28
= Initial angular velocity = 95 rad/s
= Angle of rotation
= Final angular velocity
t = Time taken
Angular acceleration is given by
The angular acceleration is -24.28571 rad/s²
The number of revolutions is 29.57239
The time it takes for the car to stop is 3.91176 seconds
Linear distance
The distance the car travels is 52.026478 m
Answer:
The distance the log has moved by the time Ernie reaches Bur is 1.33 m.
Explanation:
give information:
The log is 3.0 m long and has mass 20.0 kg.
Burt has mass 30.0 kg; Ernie has mass 40.0 kg
Ernie has mass 40.0 kg.
to find the distance, first, we have to calculate the center of mass
X = ∑ m x /∑m
= (20 x (3/2)) + (30 x 0) + (40 x 3)/ (20+30+40)
= 150/90
= 5/3
when Ernie walk, the center of the mass is
X = (70 x 0) + (20 x (3/2))/(70 + 20)
= 30/90
= 1/3
the distance of log moved = 5/3 - 4/3 = 1.33 m
The displacement is the shortest distance between two points, which is 546.41. The displacement for both is 546.41 meters
Average velocity of X = (200 + 200 + 200) / 30
Average velocity of X = 20 m/s
Average velocity of Y = 546.41 / 30 = 18.2 m/s