True. Think of a magnet and how they only connect to the opposite charges.
Answer:
Explanation:
net force on the skier = mg sin 39 - μ mg cos39
mg ( sin39 - μ cos39 )
= 73 x 9.8 ( .629 - .116)
= 367 N
impulse = net force x time = change in momentum .
= 367 x 5 = 1835 kg m /s
velocity of the skier after 5 s = 1835 / 73
= 25.13 m /s
b )
net force becomes zero
mg ( sin39 - μ cos39 ) = 0
μ = tan39
= .81
c )
net force becomes zero , so he will continue to go ahead with constant speed of 25.13 m /s
so he will have speed of 25.13 m /s after 5 s .
Answer:
option (a) 0.61 s
Explanation:
Given;
Time taken by the ball to reach the ground = 0.50 s
Let us first calculate the distance through which the ball falls on the ground
from the Newton's equation of motion, we have

where,
s is the distance
a is the acceleration
t is the time
here it is the case of free fall
thus, a = g = acceleration due to gravity
u = initial speed of the ball = 0
on substituting the values, we get

or
s = 1.225 m
Now,
when the elevator is moving up with speed of 1.0 m/s
the initial speed of the ball = -1.0 m/s (as the elevator is moving in upward direction)
thus , we have

or

or
4.9t^2 - t - 1.225 = 0
or
t = 0.612 s
hence, the correct answer is option (a) 0.61 s
Answer:C
Explanation: I took the quiz if you don't believe me then your gonna miss the problem.