Answer:
x = A sin w t displacement in SHM
v = A w cos w t velocity in SHM
PE = 1/2 k x^2 = 1/2 k A^2 sin^2 w t
KE = 1/2 m v^2 = 1/2 m w^2 A^2 cos^2 w t
If KE = PE then
k sin^2 w t = m w^2 cos^2 w t
sin^2 wt / cos^2 w t = tan^2 w t = m w^2 / k
but k / m = w^2
So tan^2 w t = 1 and tan w t = 1 or w t = pi / 4 or theta = 45 deg
Then x = r sin w t = r sin 45 = .707 r
In this case, the movement is uniformly delayed (the final
rapidity is less than the initial rapidity), therefore, the value of the
acceleration will be negative.
1. The following equation is used:
a = (Vf-Vo)/ t
a: acceleration (m/s2)
Vf: final rapidity (m/s)
Vo: initial rapidity (m/s)
t: time (s)
2. Substituting the values in the equation:
a = (5 m/s- 27 m/s)/6.87 s
3. The car's acceleration is:
a= -3.20 m/ s<span>^2</span>
-- a party balloon that's full of helium and resting on the ceiling
-- a piece of styrofoam
-- a cloud of smoke
-- a bag of hot air
-- a cirrus cloud in the sky
Answer:
632 nm
Explanation:
For constructive interference, the expression is:
Where, m = 1, 2, .....
d is the distance between the slits.
The formula can be written as:
....1
The location of the bright fringe is determined by :
Where, L is the distance between the slit and the screen.
For small angle ,
So,
Formula becomes:
Using 1, we get:
For two fringes:
The formula is:
For first and second bright fringe,
Given that:
d = 0.200 mm
L = 5.00 m
Also,
1 cm = 10⁻² m
1 mm = 10⁻³ m
So,
d = 0.2×10⁻³ m
Applying in the formula,
Also,
1 m = 10⁹ nm
<u>So wavelength is 632 nm</u>
Answer:
Friction acts in the opposite direction to the motion of the truck and box.
Explanation:
Let's first review the problem.
A moving truck applies the brakes, and a box on it does not slip.
Now when the truck is applying brakes, only it itself is being slowed down. Since the box is slowing down with the truck, we can conclude that it is friction that slows it down.
The box in the question tries to maintains its velocity forward when the brakes are applied. We can think of this as the box exerting a positive force relative to the truck when the brakes are applied. When we imagine this, we can also figure out where the static friction will act to stop this positive force. Friction will act in the negative direction. Or in other words, friction will act in the opposite direction to the motion of the truck and box. This explains why the box slows down with the truck, as friction acts to stop its motion.