Answer: 760 N
Weight is the force acting on the body due to gravity. This weight is shown by weighing scale which measures the normal force acting against the gravitational pull when the person stands on it.
When Lucy stands on the weighing scale, net force due to gravity is
Hence, weight of Lucy is 760 N
Answer:
518400 Newton
Explanation:
Force F = mass m * Acceleration a
a = velocity v / time t
v = distance d / t
Therefore;
F = m * v² / d
with m = 2000 (unit not defined but say g)
v = 144 Km/h
d = 80 meters =0.08Km
F = 2Kg * 144Km/h * 144Km/h / 0.08Km
F = 518400 Newton
Answer:
(a) I_A=1/12ML²
(b) I_B=1/3ML²
Explanation:
We know that the moment of inertia of a rod of mass M and lenght L about its center is 1/12ML².
(a) If the rod is bent exactly at its center, the distance from every point of the rod to the axis doesn't change. Since the moment of inertia depends on the distance of every mass to this axis, the moment of inertia remains the same. In other words, I_A=1/12ML².
(b) The two ends and the point where the two segments meet form an isorrectangle triangle. So the distance between the ends d can be calculated using the Pythagorean Theorem:
Next, the point where the two segments meet, the midpoint of the line connecting the two ends of the rod, and an end of the rod form another rectangle triangle, so we can calculate the distance between the two axis x using Pythagorean Theorem again:
Finally, using the Parallel Axis Theorem, we calculate I_B:
Initial velocity = 5mph
final velocity = 7mph