Complete question:
The coordinate of a particle in meters is given by x(t)=1 6t- 3.0t³ , where the time tis in seconds. The
particle is momentarily at rest at t is:
Select one:
a. 9.3s
b. 1.3s
C. 0.75s
d.5.3s
e. 7.3s
Answer:
b. 1.3 s
Explanation:
Given;
position of the particle, x(t)=1 6t- 3.0t³
when the particle is at rest, the velocity is zero.
velocity = dx/dt
dx /dt = 16 - 9t²
16 - 9t² = 0
9t² = 16
t² = 16 /9
t = √(16 / 9)
t = 4/3
t = 1.3 s
Therefore, the particle is momentarily at rest at t = 1.3 s
Answer:
Wave W is a sound wave, Waves X and Y are light waves, and it is impossible to tell what kind of wave Wave Z is.
Explanation:
W travels fastest through metal
X travels fastest through air,
Y travels more slowly through water than air
Z travels more slowly at cool temperatures
W appears to be sound wave as sound travels fastest through metal .
X appears to be light wave as light travels fastest in air .
Y also appears to be light wave as speed of light is reduced when it passes from air to water .
Z It is impossible to tell anything about the nature of Z wave .
Answer:
a and b.
Explanation:
In general types of wave
1. Transverse wave :
In these waves particle are vibrate perpendicular to motion of waves.
Ex : Electromagnetic wave , Radio wave .
2. Longitudinal wave :
In these waves particle are vibrate along the motion of waves.
Ex : Sound wave
Mechanical wave :
1 .These are transverse wave or Longitudinal wave or combination of them .
2.These waves required medium for propagation.
3. The particle are vibrate perpendicular to motion of waves.
So the option a and b are correct.
Answer:
Explanation:
area of square loop A = side²
= 8.4² x 10⁻⁴
A = 70.56 x 10⁻⁴ m²
when it is converted into rectangle , length = 14.7 , width = 2.1
area = length x width
= 14.7 x 2.1 x 10⁻⁴
= 30.87 x 10⁻⁴ m²
Let magnetic field be B
Change in flux = magnetic field x change in area
= B x ( 70.56 x 10⁻⁴ - 30.87 x 10⁻⁴ )
= 39.69 x 10⁻⁴ B
rate of change of flux = change in flux / time taken
= 39.69 x 10⁻⁴ B / 6.5 x 10⁻³
= 6.1 x 10⁻¹ B
emf induced = 6.1 x 10⁻¹ B
6.1 x 10⁻¹ B = 14.7 ( given )
B = 2.41 x 10
= 24.1 T
B ) magnetic flux is decreasing , so it needs to be increased as per Lenz's law . Hence current induced will be anticlockwise so that additional magnetic flux is induced out of the page.
Answer:
Order of maximum transmission of the polarizer is A, C and B.
Solution:
As per the question:
For the first polarizer, the angle is quite insignificant:
(A) 
:
The light intensity after passing through the first polarizer is 
and this intensity does not depend on the angle of the polarizer.
Consider with the vertical, the intensity is given by:
(B) 
:
Suppose the second polarizer is 
with the vertical.
Now, intensity through the second polarizer:
Now, if we consider the second polarizer to be ,
(C) 
:
Now,
Intensity through the third polarizer, if it is with the vertical:
