Answer:
Explanation:
Let us calculate the average velocity .
Average velocity = total distance / total time
Time taken to drive first 15 mi
= 15 / 60 = .25 h
Time taken to drive next 15 mi
= 15 / 30 = .5 h
Total time = .25 + .5 = .75 h
Total distance = 30 mi
average speed = 30 / .75
= 40 mi / h
So average speed is 40 mph which is less than given velocity of 45 mph .
Hence if she travels at 45 mph , she will take less time .
Answer:
option E
Explanation:
given,
I is moment of inertia about an axis tangent to its surface.
moment of inertia about the center of mass
.....(1)
now, moment of inertia about tangent
...........(2)
dividing equation (1)/(2)
the correct answer is option E
Answer:
Inclined plane.
Explanation:
Geometrically, a screw is a narrow inclined plane that is wrapped around a cylinder. Like the other simple machines a screw can amplify force; a small rotational force (torque) on the shaft can exert a large axial force on a load.
A screw is a cylinder with a head (solid top) at one end and a pointed tip (like a nail) at the other end.
The mechanical advantage of the screw depends on the space between the threads and the length (and thickness) of the screw. The closer the threads are, the greater the mechanical advantage. It is easier to drive a screw into an object if the thread spacing is smaller.
Answer:
physical quantity that only has magnitude and no other characteristics.
Explanation:
so no velocity only magnitude
