Answer:
285 seconds
Explanation:
Jenny speed is 3.8 m/s
Alyssa speed in 4.0 m/s
Alyssa starts after 15 seconds
Find the distance covered by Jenny, when Alyssa starts
Distance=Speed*time
Distance covered by Jenny in 15 seconds= 3.8×15=57m
Relative speed of the two members heading same direction will be;
4.0m/s-3.8m/s=0.2m/s
To find the time Alyssa catch up with Jenny you divide the distance to be covered by Alyssa by the relative speed of the two
Distance=57m, relative speed=0.2m/s t=57/0.2 =285 seconds
=4.75 minutes
Answer:
E)
Explanation:
Because of Newton's Second Law, which says any action will be opposed by a reaction of the same magnitude, then no matter what, no matter if the box does or does not move, the bat bouces back, or what happens after the hit, when hitting the box the force ithbox exerts on the bat is exactly 1500 N.
Answer:
8000 kg/m^3
Explanation:
Weight in air = 7.84 n
Weight in water = 6.86 N
density of water = 1000 kg/m^3
Let d be the density of object
According to the Archimedes principle, when a body is immersed in a liquid partly or wholly, it experiences an upward force which is called buoyant force. The buoyant force is equal to the loss in weight of the body.
Loss in weight of the object = Weight of object in air - weight of object in water
Loss in weight = 7.84 - 6.86 = 0.98 N
Volume of body x density of water x g = 0.98
Let V be the volume of body
V x 1000 x 9.8 = 0.98
V = 10^-4 m^3
Weight in air = Volume of body x density of body x g
7.84 = 10^-4 x d x 9.8
d = 8000 kg/m^3
Thus, the density of body is 8000 kg/m^3.
