Answer:
450 joules ; 450 joules ; 45.9 m
Explanation:
Given that :
Initial Velocity, u = 30m/s
Mass, m = 1 kg
Kinetic Energy of ball (KE) = 0.5mu²
K. E = 0.5 * 1 * 30^2
K.E = 0.5 * 900
K.E = 450 Joules
B.) Potential Energy (P. E)
P. E = mgh
At the highest point, all kinetic energy has would have become potential energy, hence
K. E = P. E = 450 Joules
C) Height of the ball :
From ; P. E = mgh
Where ; g = acceleration due to gravity = 9.8m/s² ; h = height
450 = 1 * 9.8 * h
450 = 9.8h
h = 450 / 9.8
h = 45.918
h = 45.9 m
M = 4kg
F =8N
a..?
F =m.a
8 = 4.a
a = 2m/s^2
Displacement (between time 0 and time 25) is the area under the velocity time curve, i.e. ∫ vdt.
Here, v(0)=10, v(25)=34 (approx.)
Therefore
displacement = (1/2)(10+34 m/s)*(25-0) s [ trapezoid area ]
=550 m
Answer: The correct answer is zero work done.
Explanation:
Work is said to be done when the object moves through a distance when the force is applied to the object.
If the object does not move a distance even the force is exerted on the object then the work done is zero in this case.
Therefore, when the force is exerted even when no work is done then this is called zero work done.
Answer:
61.85 ohm
Explanation:
L = 12 m H = 12 x 10^-3 H, C = 15 x 10^-6 F, Vrms = 110 V, R = 45 ohm
Let ω0 be the resonant frequency.
ω0 = 2357 rad/s
ω = 2 x 2357 = 4714 rad/s
XL = ω L = 4714 x 12 x 10^-3 = 56.57 ohm
Xc = 1 / ω C = 1 / (4714 x 15 x 10^-6) = 14.14 ohm
Impedance, Z = 
Z = \sqrt{45^{2}+\left ( 56.57-14.14 )^{2}} = 61.85 ohm
Thus, the impedance at double the resonant frequency is 61.85 ohm.
