The part of a river that would have animals with muscular bodies and adaptations that let survive in turbulent water is in the transition zone, the mid-transition zone to be precise.
Water at the source zone possesses a lot of potential energy and as it flows from the upper reaches the potential energy is turned into kinetic energy when the course of the river begins to gradually level out and this translates into increase in velocity. By the time river water reaches the middle of the transition zone, most of the potential energy would have been turned into kinetic energy and thus water velocity would be quite high here.
Animals living here would develop muscles because of constantly fighting against the strong current to avoid being swept downstream.
You have to solve this by using the equations of motion:
u=3
v=0
s=2.5
a=?
v^2=u^2+2as
0=9+5s
Giving a=-1.8m/s^2
Then using the equation:
F=ma
F is the frictional force as there is no other force acting and its negative as its in the opposite direction to the direction of motion.
-F=25(-1.8)
F=45N
Then use the formula:
F=uR
Where u is the coefficient of friction, R is the normal force and F is the frictional force.
45=u(25g)
45=u(25*10)
Therefore, the coefficient of friction is 0.18
Hope that helps
Answer:60 gm
Explanation:
Given
initial velocity of ball
Force exerted by racquet
time period of force
final velocity of ball
Racquet imparts an impulse to the ball which is given by
Answer: T is greater
Explanation:
Since the elevator is moving against gravity more work will be done on the rope
T= m(g+a)
During the falling down, two forces are present: gravitational force and air resistance.
So, the net force = mg - f = 12*9.8 - 27 = 90.6 N, the positive sign indicates the direction is pointing towards the center of the earth, which is the same as gravitational force