Answer: A.AB
Explanation:
This Velocity vs Time graph shows the acceleration of a body or object, since acceleration is the variation of velocity in time.
As we can see in the attached image, the graph can be divided in four segments:
OA: In this segment the acceleration is changing at a uniform rate. In addition we can see it has a positive slope, hence we are dealing with a positive uniform acceleration.
AB: In this segment the acceleration is changing at a nonuniform rate, since in this part it is not possible to calculate the slope. However if this were uniform, the slope woul be positive. This means the <u>acceleration is nonuniform and positive.</u>
BC: In this segment the acceleration is changing at a nonuniform rate, since in this part it is not possible to calculate the slope. However if this were uniform, the slope woul be negative. This means the acceleration is nonuniform and negative.
CD: In this segment the acceleration is changing at a uniform rate. In addition we can see it has a negative slope, hence we are dealing with a negative uniform acceleration.
From all these segments, the only one that fulfils the nonuniform positive acceleration condition is option A:
Segment AB
Answer:
C. 12m
Explanation:
from the graph v = 4m/s and t = 3 s
d = vt = 4 × 3 = 12 m
Answer: For the first part the answer is Radio Waves and the second part’s answer is gamma ray.
Net force acting on mass = 20 - 15 = 5N. ( subtracted cuz friction always opposes the motion i.e it always acts in direction opposite to the motion of the object). According to Newton's 2nd law of motion, F(net) = ma. a =F (net) / m = 5/10 = 0.5 m/s^2. Hope it helps :)
Answer:
a) λ = 2 m
, c) f = 50 Hz
Explanation:
When a string is fixed at the ends the wave is reflected at each end, giving rise to a standing wave.
Since we extract them are fixed we have nodes at these points, the wavelength in the string is
fundamental λ = 2L
2nd harmonic λ= 2L / 2
3 harmonica λ= 2L / 3
a and b) from aui we can find the wavelength
λ = 2 3/3
λ = 2 m
c) the speed of the wave is related to the frequency and wavelength
v = λ f
f = v / λ
f = 100/2
f = 50 Hz
d) the acceleration can be found with the equations
a = d²y / dt²
the standing wave equation is
y = 2A sin kx cos wt
a = -2A w² sin kx cos wt
the acceleration is maximum when the cosine is ±1
A = 2A w² sin kx
the oscillatory part indicates that the wave moves, if we make this maximum vine, they relate it to
a = 2A w²
w = 2πf
A = 0.2 cm = 0.002 m
a = 2 0.002 (2π 50)²
a = 98.7 m / s
