Answer:

Explanation:
given,
refractive index of lens, n = 1.70
Radius of curvature of front surface. R₁ = 20 cm
Radius of curvature of the back surface, R₂ = 30 cm
focal length= ?

R₁ = +20 cm
R₂ = -30 cm
n = 1.70




the focal length of the lens is equal to 17.15 cm
Answer:
Explanation:
Although there is absolutely NO regard for significant digits, I can help you with this, nonetheless.
The equation for Potential Energy is PE = mgh. We have everything but the height of the ball. We have to solve for that using a one-dimensional motion equation:
v² = v₀² + 2aΔx, where Δx is our displacement (the height we need for PE). Filling in and keeping in mind that at the max height of parabolic travel, the final velocity of the object is 0:
0 = (21.5)² + 2(-9.8)Δx and
0 = 462.25 - 19.6Δx and
-462.25 = -19.6Δx so
Δx = 23.58 m. Using this as the h in our PE equation:
PE = .19(9.8)(23.58) so
PE = 43.9 J, choice C.
Answer: The atmosphere of trophic rainforest is hot and humid due to high rate of transpiration.
Explanation:
The tropical rainforest is a biome which exhibit rich biodiversity of plants and animals. The average temperatures in this region remain high with warm summer. It remains frost free. The soil is nutrient deficient. Due to hot temperature the rate of transpiration remains high as a result the concentration of the water vapors remain high. This is responsible for increasing the humidity in the atmosphere also this region receives appreciable amount of rainfall annually. The average rainfall range is 200-450 centimeters.
Te direction of the magnetic force for the velocity of the proton in the
-ve y direction will be +ve z direction.
As we know that the right-hand rule is based on the relation of magnetic fields and the forces that they exert on moving charges.When a charged particle moves under a magnetic field, it exerts a force on the particle, which is not in the same direction but different than the direction of the magnetic field.Under the right-hand rule, if we point our pointer finger in the direction of the charged particle is moving and the middle finger is representing the direction of the magnetic field then our thumb depicts the direction of the magnetic force which is exerted on the charged particle.
So, we are given that the direction of the velocity of the proton is in the negative y direction and the direction of the magnetic field is in the positive x direction, so the magnetic force is acting in the positive z direction.
To know more about the right-hand rule refer to the link brainly.com/question/9750730?referrer=searchResults.
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