Answer:
Weight required = 194.51 N
Explanation:
The elongation is given by
Length , L= 1.6 m
Diameter, d = 1.1 mm
Area
Change in length, ΔL = 2.8 mm = 0.0028 m
Young's modulus of copper, E = 117 GPa = 117 x 10⁹ Pa
Substituting,
Weight required = 194.51 N
Answer:
(a) -8064 N
(b) 8064 N
Explanation:
(a)
From Newton’s law of motion, Force, F=ma where m is mass and a is acceleration.
Since acceleration is the rate of change of velocity per unit time, then where v is velocity and the subscripts f and I denote final and initial
For the first ball, the mass is 0.28 Kg, final velocity is zero since it finally comes to rest, t is 0.00025 s and initial velocity is given as 7.2 s. Substituting these values we obtain
(b)
For the second ball, the mass is also 0.28 Kg but its initial velocity is taken as zero, the final velocity of the second ball will be equal to the initial velocity of the second ball, that is 7.2 m/s and the time is also same, 0.00025 s. By substitution
Here, we prove that action and reaction are equal and opposite
Answer:
a. The component of the net force which make up the apparent weight are added to each other at the bottom and subtracted (the centripetal force from the weight) at the top)
b. Apparent weight at the top is approximately 519.06 N
Apparent weight at the bottom is approximately 558.94 N
Explanation:
a. The apparent weight at the top is different from the apparent weight at the bottom of a moving Ferris wheel because of the opposite direction in which the centripetal force acts at the top and the bottom, which are upwards and downwards respectively, while the weight acts downwards constantly
b. The given parameters are
The radius of the Ferris wheel, r = 7.2 m
The period for one complete revolution, t = 28 seconds
The angle covered in one revolution, θ = 2·π radian
The mass of the person riding on the Ferris wheel, the passenger = 55 kg
Therefore, we have;
The angular speed, ω = Δθ/Δt = 2·π/(28)
From which we have;
Centripetal force, = m × ω² × r
Substituting the known values, we have = 55 kg × (2·π/(28 s))² × 7.2 m ≈ 19.94 N
The centripetal force, = 19.94 N always acting outward from the center
Weight = Mass × Acceleration due to gravity
The weight of the passenger = 55 kg × 9.8 m/s² = 539 N
The weight of the passenger = 539 N always acting downwards
At the top of the Ferris wheel the the centripetal force is acting upwards and the weight is acting downwards
Therefore;
The net force, which is the apparent weight of the passenger at the top = 539 N - 19.94 N ≈ 519.06 N
Apparent weight at the top ≈ 519.06 N
At the bottom of the Ferris wheel the weight is acting downwards and the centripetal force is also acting downwards
Therefore;
The net force at the bottom, which is the apparent weight of the passenger at the bottom = 539 N + 19.94 N ≈ 558.94 N
Apparent weight at the bottom ≈ 558.94 N.
Answer: Period T = 4.44secs
Explanation: see attachment
