Answer:
the answer is
Explanation:For equilibrium
Weight = Tension
mg=T
∴T=4×3.1π=12.4πN (as can be inferred from the question)
Y=
△l/l
T/A
=
1000
0.031
/20
12.4π/π(
1000
2
)
2
=
4×0.031
12.4×20×1000×(1000)
2
=2×10
12
N/m
2
Hiiiii friends......
here is your answer.....
✌✌ Resistive force is a force where direction is opposite to the velocity of body or the sum of the other force and may refer to friction
now force lost by the machine
Answer:
The speed of the electron is 1.371 x 10⁶ m/s.
Explanation:
Given;
wavelength of the ultraviolet light beam, λ = 130 nm = 130 x 10⁻⁹ m
the work function of the molybdenum surface, W₀ = 4.2 eV = 6.728 x 10⁻¹⁹ J
The energy of the incident light is given by;
E = hf
where;
h is Planck's constant = 6.626 x 10⁻³⁴ J/s
f = c / λ
Photo electric effect equation is given by;
E = W₀ + K.E
Where;
K.E is the kinetic energy of the emitted electron
K.E = E - W₀
K.E = 15.291 x 10⁻¹⁹ J - 6.728 x 10⁻¹⁹ J
K.E = 8.563 x 10⁻¹⁹ J
Kinetic energy of the emitted electron is given by;
K.E = ¹/₂mv²
where;
m is mass of the electron = 9.11 x 10⁻³¹ kg
v is the speed of the electron
Therefore, the speed of the electron is 1.371 x 10⁶ m/s.
Answer:
Option C
Explanation:
given,
velocity of airplane = 80 m/s
angle with the horizontal = 15°
speed of the ground= ?
when the plane is taking off the horizontal component of the velocity is v cosθ
so,
ground speed of the airplane is = 
= 
v = 77.27 m/s
horizontal velocity of the air plane comes out to be 77.27 m/s ≅ 77 m/s
so, the correct option is Option C
Answer:
The scientific method is the process by which scientists gain confidence in theories by failing to prove them wrong.
Explanation:
Scientific method is a step by step process of creating and carrying out experiments. These processes to be performed are derived from logical and rational application of knowledge concerning a particular subject matter. Through these processes, scientists reach a conclusion about the world, these makes them confident in their findings.
The steps involved in scientific method include:
Observation: it is the first step. It enables you organise in your mind how you want the experiment to.
HYPOTHESIS is the result you imagine you'll find.
PREDICTION is how you think about the scientific idea- It solely relies on the hypothesis made.
EXPERIMENT is used to test your hypothesis. It is the tool designed to check if your idea is right or wrong.
CONCLUSION is the final step. It is the result gotten from the experiment. It can approve the hypothesis or reject the hypothesis.
A theory is formed when hypothesis has been tested to be true by many scientists. Hence scientists gain confidence in theories when the scientific method is approved.
A scientific theory is a well-approved explanation of an aspect of the natural world. The approval is based on thoroughly confirmed hypothesis and experiments carried out by many scientists.
