Answer:
24.71 mm
Explanation:
Distance is proportional to focal length, so
d∝f
which means
Magnification of first lens
and
Similarly, magnification of second lens
and
From the above equations we get
and
which means,
and
So, we get
∴ Focal length should this camera's lens is 24.71 mm
Answer: ∆L = 0.49cm ≈ 0.50cm
Therefore there should be 0.5 cm gap between each piece of steel.
Explanation:
Thermal expansion of steel is the increase in size of steel as a result of increased temperature. It can be represented by the mathematical expression:
∆L = L(k)∆T .....1
Where;
∆L is the change in length
L is the initial length
∆T is the change in temperature
k is the specific Linear expansion coefficient.
Given;
L = 12m
∆T = 50°C - 16°C = 34°C
k (for steel) = 1.2 × 10^-6 /C
Substituting the values into the equation 1
∆L = 12 × 34 × 12×10^-6
∆L = 4896 × 10^-6 m
∆L = 0.49cm ≈ 0.50cm
Therefore there should be 0.5 cm gap between each piece of steel.
Answer: find the answer in the explanation
Explanation:
Average velocity is the average value of magnitude of initial velocity and final velocity.
If U = initial velocity and V = final velocity, then average velocity can be expressed as
Average velocity = ( U + V )/2
A vehicle who takes 60 minutes to cover 30 miles north and then 30 miles south and end up at the same place, has an average speed of 60 miles divided by 60 minutes, or 1 mile per minute.
Instantaneous velocity is the distance covered in a specific direction per time taken. Instantaneous velocity can be expressed as
Velocity = displacement/ time.
Uniform velocity occurs when we have a constant velocity. That is, when velocity does not change. When a vehicle travels in equal distances in equal intervals of time.
Answer:
Zero gravity
Explanation:
Astronauts around the earth either in spaceship, a space station or on a space walk appear to be weightless because of the zero gravity in such environment.
Weight is a function of the mass and acceleration due to gravity a body has.
Weight = mass x acceleration due to gravity
In a place where acceleration due to gravity is 0, the weight would be zero and a person would appear to be weightless.
No the vector can never be shorter than one of its components
