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3 years ago

A lens is transparent material with _____.

2 answers:

7 0

I think the correct answer from the choices listed above is option C. A lens is transparent material with one or two curved surfaces that can refract light. A lens is made of a transparent material having an index of refraction of 2.0. One side of the lens is flat, and the other convex with a radius of curvature of 25 cm.

Vsevolod [243]3 years ago

6 0

Answer:

one or two curved surfaces that can refract light

Explanation:

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A bat can detect small objects, such as an insect, whose size is approximately equal to one wavelength of the sound the bat make

blsea [12.9K]

Answer:

6.136 mm

Explanation:

given,

frequency emitted by the bat = 5.59 x 10⁴ Hz

speed of sound = 343 m/s

smallest insect bat can hear will be equal to the wavelength of the sound the bat make.

$\lambda = \dfrac{v}{f}$

$\lambda = \dfrac{343}{5.59\times 10^4}$

$\lambda = 6.136\times 10^{-3}}$

λ = 6.136 mm

so, the smallest size of insect that bat can hear is equal to 6.136 mm

8 0

3 years ago

Read 2 more answers

The two forces in each pair can either both act on the same body or they can act on different bodies. The two forces in each pai

kotykmax [81]

Answer: The given statement is false.

Explanation:

According to Newton's third law of motion, every action has an equal and opposite reaction. So, when we apply force in one direction on an object then the object also applies a force in the opposite direction.

Hence, it is true that two forces in each pair of forces act in opposite directions.

For example, when we push a wooden box of 20 kg in the forward direction then the box will also apply a force in the opposite direction.

But the statement two forces in each pair can either both act on the same body or they can act on different bodies is false.

5 0

3 years ago

Which of the following is NOT true about the structure of the nucleus? a. The nucleus is filled with cytoplasm b. The nucleus ha

Cerrena [4.2K]

Answer:

A. The nucleaus is filled with cytoplasm OR d. The nucleus is by a double layer membrane.

Explanation:

b. and c. are true and I'm certain they are true

a. I know the inside of a cell has cytoplasm but I'm not sure if the inside of a nucleus is filled with cytoplasm. And d. I'm not so sure, so it's either a or d. Hope this helps!

3 0

3 years ago

Hello....I need help with this question.

musickatia [10]

Answer:

3.2 m/s²

Explanation:

Acceleration can be calculated as:

v = u + at (where v is final velocity, u is initial velocity, a is acceleration and t is time)

25 m/s = 9 m/s + a(5 s) (a is unknown)

16 m/s = a(5 s)

a = 3.2 m/s²

We assume that this is a uniform acceleration (meaning that the velocity increases at an equal rate for those 5 seconds).

6 0

3 years ago

Read 2 more answers

The force exerted by an electric charge at the origin on a charged particle at a point (x, y, z) with position vector r = x, y,

kap26 [50]

$W = K[ {\frac{1}{3} - \frac{1}{\sqrt{38} } ]$

Explanation:

The parametric representation of a line segment joining the points (a,b,c) and (l,m,n) is

r(t) = (1-t) . (a,b,c) + t . (l, m, n) where t ∈ |0, 1|

So, the parametric representation of a line segment joining the points (3,0,0) and (3,2,5) is

r(t) = (1 - t) . (3,0,0) + t . (3,2,5) where t ∈ |0, 1|

r(t) = (3(1 - t), 0, 0) + (3t, 2t, 5t) where t ∈ |0, 1|

r(t) = (3, 2t, 5t)

Given:

$F(x, y, z) = \frac{Kr}{|r|^3} \\\\F(x, y, z) = \frac{K}{(x^2 + y^2 + z^2)^3^/^2} (x, y, z)\\\\F(r(t)) = \frac{K}{(3^2 + (2t)^2 + (5t)^2)^3^/^2} (3, 2t, 5t)\\\\F(r(t)) = \frac{K}{(9 + 29t^2)^3^/^2} (3, 2t, 5t)$

dr = (0, 2, 5) dt

$Work = \int\limits^1_0 {F} \, dr$

$W = \int\limits^1_0 {\frac{K}{(9 + 29t^2)^3^/^2} } (3, 2t, 5t) . (0, 2, 5)\, dt\\ \\ = \int\limits^1_0 {\frac{K ( 4t + 25t)}{(9 + 29t^2)^3^/^2} } \, dt\\\\\\$

$W = \frac{1}{2}\int\limits^1_0 {\frac{K(29t)}{(9 + 29t^2)^3^/^2} } \, dt \\ \\$

Substitute = 9 + 29t² = u, 92tdt = du

Limit changes from 0→1 to 9 → 38

$W = \frac{K}{2} \int\limits^3_9 {\frac{du}{u^3^/^2} } \,\\\\$

On solving this, we get:

$W = K[ {\frac{1}{3} - \frac{1}{\sqrt{38} } ]$

Therefore, work done is $W = K[ {\frac{1}{3} - \frac{1}{\sqrt{38} } ]$

5 0

3 years ago