Answer:
The answer is A
Explanation:
When a rockets thrusters push on the ground the ground pushes back on the rocket with equal force in the opposite direction. Hence the rocket takes off.
Newtons third law of motion states, for every action there is an equal and opposite reaction.
Answer:
The answer to your question is Pe = 2452.5 J
Explanation:
Data
mass = 50 kg
height = 5 m
gravity = 9.81 m/s²
Process
The energy of this process is Potential energy which is proportional to the mass of the body, the gravity and the height of the body.
Pe = mgh
Substitution
Pe = (50)(5)(9.81)
Simplification
Pe = 2452.5 J
Answer:
"Magnitude of a vector can be zero only if all components of a vector are zero."
Explanation:
"The magnitude of a vector can be smaller than length of one of its components."
Wrong, the magnitude of a vector is at least equal to the length of a component. This is because of the Pythagoras theorem. It can never be smaller.
"Magnitude of a vector is positive if it is directed in +x and negative if is is directed in -X direction."
False. Magnitude of a vector is always positive.
"Magnitude of a vector can be zero if only one of components is zero."
Wrong. For the magnitude of a vector to be zero, all components must be zero.
"If vector A has bigger component along x direction than vector B, it immediately means, the vector A has bigger magnitude than vector B."
Wrong. The magnitude of a vector depends on all components, not only the X component.
"Magnitude of a vector can be zero only if all components of a vector are zero."
True.
Answer:
U² = 142.86 N
U¹ = 357.14 N
Explanation:
Taking summation of the moment about point A, we get the following equilibrium equation: (taking clockwise direction as positive)
where,
W = weight of boy = 500 N
U² = reaction ay B = ?
Therefore,
<u>U² = 142.86 N</u>
Now, taking summation of forces on the plank. Taking upward direction as positive, for equilibrium position:
<u>U¹ = 357.14 N</u>
Answer:
Explanation:
The problem is based on interference in thin films
refractive index of water is more than given oil so there will be phase change of π at upper and lower layer of the film .
a )
for constructive interference , the condition is
2μt = nλ where t is thickness of layer , μ is refractive index , λ is wavelength and n is order of the fringe
Putting the values
2 x 1.27 t = n x 640
2 x 1.27 t = 640 ( for minimum thickness n = 1 )
t = 252 nm .
b )
2 x 1.27 t = m₁ λ₁
for destructive interference
2μt = (2m₂+1)λ₂/2
2 x 1.27 t =(2m₂+1)λ₂/2
m₁ λ₁ = (2m₂+1)λ₂/2
2m₁λ₁ = (2m₂+1)λ₂
2m₁ / (2m₂+1) = λ₂ / λ₁
2m₁ / (2m₂+1) = 548/ 640
2m₁ / (2m₂+1) = .85625
2m₁ = .85625 (2m₂+1)
This is the required relation between m₁ and m₂
