The restoring force of the spring cancels the weight of the mass, so by Newton's second law
∑ F = F[spring] - mg = 0 ⇒ F[spring] ≈ 45.1 N
where m = 4.60 kg and g = 9.80 m/s². Then the spring constant is k such that by Hooke's law,
F[spring] = k x
where x = 0.0231 m. Then the spring constant is
k = F[spring]/x ≈ 1950 N/m
Answer: 7.07 m/s
Explanation:
Mass of runner = 60 kg runner
Kinetic energy = 1500J
Speed of runner = ?
Recall that kinetic energy is the energy possessed by a moving object, and it depends on its mass and speed by which it moves.
Hence, K.E = 1/2 x mass x (speed)^2
1500J = 1/2 x 60kg x (speed)^2
1500J = 30kg x (speed)^2
(speed)^2 = 1500J/30kg
(speed)^2 = 50
To get the value of speed, find the square root of 50
speed = √50
speed = 7.07 m/s
Thus, the runner moves as fast as 7.07 m/s
Answer:
A. Conservation of energy.
Explanation:
Kirchhoff's loop rule is an example of conservation of energy.
Answer:
Pendulum B
Explanation:
The time period of a pendulum is given by :
Case 1.
Mass, m = 200 g = 0.2 kg
Length of string, l = 1 m
Time, 
T₁ = 2.007 Seconds
Since, 
f₁ = 0.49 Hz
Case 2.
Mass, m = 400 g = 0.4 kg
Length of string, l = 0.5 m
Time, 
T₂ = 1.41 seconds
f₂ = 0.709 seconds
Hence, pendulum B have highest frequency of vibration.
Answer:
True.
Explanation:
The density of an object is given by its mass divided by its volume. It can be given as follows :
It can be seen that the density of an object is directly proportional to its mass. It means if the mass of an object increase, its density will also increase. Hence, the given statement is true.
