The focal length of the lens is the distance between the lens and the image sensor when the subject is in focus, usually stated in millimeters (e.g., 28 mm, 50 mm, or 100 mm). In the case of zoom lenses, both the minimum and maximum focal lengths are stated, for example 18–55 mm.
The speed of a car travelling over a hill that has a radius of curvature should not exceed a certain speed other it will topple. This speed is related to the radius of curvature and the gravitational acceleration as shown below:
V^2 = Rg, where V = maximum speed, R = Radius of curvature, g = gravitational acceleration.
Substituting;
V = Sqrt (Rg) = Sqrt (120*9.81) = 34.31 m/s
Answer:
When the bat hits the ball, it exerts some force on the ball. Just think about a home run hitter hitting a stationary ball. How far do you think it will go? Will it go more than 400 ft.? Probably not. While the kinetic energy transferred from the bat to the ball accounts for some energy of the ball, it does not account for all. Where is the mysterious energy coming from?
The answer is conservation of momentum. I just said momentum is conserved but how do I know that? I know that because of Newton's 2nd law: F=ma (Force equals mass times acceleration)
Conservation of momentum means that the harder you throw you, the harder the ball will bounce back at you. That is the reason it is easier to hit a home run on a fast ball than a curveball.
Conservation of momentum also means that the bat can transfer some of its momentum to the ball. This is why it is better to use a heavier bat if you swing just as fast. The momentum is the product of the mass and velocity, so to make it easier to understand;
a heavier bat swung at the same speed as a lighter bat will have more momentum.
Answer:
Explanation:
Given
when resistance in Parallel
Suppose V is voltage of battery
Total Current 
Since Circuit is Parallel therefore Voltage across both resistor is same
and 
(b) When Circuit is in series
since circuit is in Series therefore current is same in both resistor
Current 
Voltage drop across 
Answer:
x = 2.69 cm
Explanation:
We are given ;
Density of oil; ρ_oil = 924 kg/m³
Density of wood; ρ_wood = 970 kg/m³
h = 3.79cm
Density of water ( ρ_water) has a constant value of 1000 kg/m³
At equilibrium position, we have;
ρ_wood•g•h - ρ_oil•g•(h - x) - ρ_water•g•x = 0
This is because the density of oil is lower than that of water while density of wood is higher than that of oil but lower than that of water.
x is the distance below the interface between the two liquids is the bottom of the block.
Thus, let's make x the subject;
x = [(ρ_wood - ρ_oil)/(ρ_water - ρ_oil)] x h
Plugging in the relevant values to get ;
x = [(970 - 924)/(1000 - 924)] x 3.79
x = (54/76) x 3.79 = 2.69cm
