Answer:
3.46 seconds
Explanation:
Since the ball is moving in circular motion thus centripetal force will be acting there along the rope.
The equation for the centripetal force is as follows -
Where, 
is the mass of the ball, 
is the speed and 
is the radius of the circular path which will be equal to the length of the rope.
This centripetal force will be equal to the tension in the string and thus we can write,
and, 
Thus, 
m/s.
Now, the total length of circular path = circumference of the circle
Thus, total path length = 2πr = 2 × 3.14 × 2 = 12.56 m
Time taken to complete one revolution = 
= 
= 3.46 seconds.
Thus, the mass will complete one revolution in 3.46 seconds.
Answer:
Snell's Law states
Ni sin i = Nr sin r
Judging from the question the source of the ray is in the water (directed up)
or NI = 1 / sin 49 Ni = 1.325 deg the critical angle
From inside the pond:
Nr = 1.325 * sin 45 / 1 = 94 deg
So refraction can occur outside the pond and you do not have total internal refection.
When the spring is extended by 44.5 cm - 34.0 cm = 10.5 cm = 0.105 m, it exerts a restoring force with magnitude R such that the net force on the mass is
∑ F = R - mg = 0
where mg = weight of the mass = (7.00 kg) g = 68.6 N.
It follows that R = 68.6 N, and by Hooke's law, the spring constant is k such that
k (0.105 m) = 68.6 N ⇒ k = (68.6 N) / (0.105 m) ≈ 653 N/m
Answer:
10
Explanation:
This is tough. The last number 0.2 has only one significant figure. So while the sum of all the numbers is 12.3, you must only leave one sig figure. Rounding to the tenths gives 10.
