Answer:
D) the second at the doorknob
Explanation:
The torque exerted by a force is given by:
where
F is the magnitude of the force
d is the distance between the point of application of the force and the centre of rotation
is the angle between the direction of the force and d
In this problem, we have:
- Two forces of equal magnitude F
- Both forces are perpendicular to the door, so 
- The first force is exerted at the midpoint of the door, while the 2nd force is applied at the doorknob. This means that d is the larger for the 2nd force
--> therefore, the 2nd force exerts a greater torque
Answer:
52.47706 mph
54.5 mph
Explanation:
The average speed is given by
Julie's average speed on the way to Grandmother's house is 52.47706 mph
Average speed on the return trip is 54.5 mph
Answer:
3000W
Explanation:
Given parameter:
Weight of safe = 2000N
Height of lift = 6m
Time = 4s
Unknown:
Power used by Rudolph = ?
Solution:
Power is the rate at which work is being done. It is expressed as:
Power = 
Work done = Weight x height = 2000 x 6 = 12000J
Power = 
= 3000W
Answer: Carbohydrates , proteins and lipids are large molecules that are needed by the body for growth, repair and metabolism . They are found in our food. These molecules are too large to pass from the intestine into the blood, so digestive enzymes break them down into smaller molecules.
Explanation:
