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3 years ago

Find the focal length of a lens of power-2.0D . What type of lens is this ?

Physics

1 answer:

olga_2 [115]3 years ago

3 0

Answer: f = - 0.50 m, negative (diverging) lens

Explanation: D-value (diopter ) means 1/f, unit is 1/m. Thus -2.0D

Means f = ( 1/ -2.0 ) m = -0.50 m

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Which of the following is the correct name for CCl4

Ira Lisetskai [31]

Answer: Carbon tetrachloride Or Tetrachloromethane

Explanation: Carbon tetrachloride is an important nonpolar covalent compound. You determine its name based on the atoms present in the compound.

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3 years ago

Read 2 more answers

A cheetah can run at a maximum speed 103 km/h and a gazelle can run at a maximum speed of 76.5 km/h. If both animals are running

Katena32 [7]

Answer:

$t_a = 13.49 \ s$

The distance is $D = 55.2 \ m$

Explanation:

From the question we are told that

The maximum speed of the cheetah is $v = 103 \ km/h = 28.61 \ m/s$

The maximum of gazelle is $u = 76.5 \ km/h = 21.25 \ m/s$

The distance ahead is $d = 99.3 \ m$

Let $t_a$ denote the time which the cheetah catches the gazelle

Gnerally the equation representing the distance the cheetah needs to move in order to catch the gazelle is

$v* t_a = d + u* t_a$

=> $28.61 t_a = 99.3 + 21.25t_a$

=> $7.36 t_a = 99.3$

=> $t_a = 13.49 \ s$

Now at t = 7.5 s

$7.5 v = D+ 7.5u$

=> $28.61 * 7.5 = D + 21.25* 7.5$

=> $7.36 * 7.5 =D$

=> $D = 55.2 \ m$

Hence the for the gazelle to escape the cheetah it must be 55.2 m

5 0

3 years ago

What are the different types of Energy transformations and Energy Transfers?

Harman [31]

Explanation:

Here are some of the ways that energy can change (transform) from one type to another:

The Sun transforms nuclear energy into heat and light energy.

Our bodies convert chemical energy in our food into mechanical energy for us to move.

An electric fan transforms electrical energy into kinetic energy.

7 0

4 years ago

A 90-kilogram physics student would weigh 2970 Newtons on the surface of planet X. What is the magnitude of the acceleration due

KiRa [710]

Weight = (mass) x (acceleration of gravity)

Divide each side by (mass),and we have

Acceleration of gravity = (weight) / (mass)

Acceleration of gravity = 2,970/90 = 33 newtons per kilogram = 33 m/s²

5 0

3 years ago

A body with initial velocity 8.0 m/s moves along a straight line with constant acceleration and travels

Aleksandr [31]

Answer:

(a) The average velocity is 16 m/s

(b) The acceleration is 0.4 m/s^2

(c) The final velocity is 24 m/s

Explanation:

Constant Acceleration Motion

It's a type of motion in which the velocity (or the speed) of an object changes by an equal amount in every equal period of time.

Being a the constant acceleration, vo the initial speed, vf the final speed, and t the time, final speed is calculated as follows:

$v_f=v_o+at\qquad\qquad [1]$

The distance traveled by the object is given by:

$\displaystyle x=v_o.t+\frac{a.t^2}{2}\qquad\qquad [2]$

(a) The average velocity is defined as the total distance traveled divided by the time taken to travel that distance.

We know the distance is x=640 m and the time taken t= 40 s, thus:

$\displaystyle \bar v=\frac{x}{t}=\frac{640}{40}=16$

The average velocity is 16 m/s

Using the equation [1] we can solve for a:

$\displaystyle a=\frac{v_f-v_o}{t}$

$\displaystyle a= 2\frac{x-v_ot}{t^2}$

Since vo=8 m/s, x=640 m, t=40 s:

$\displaystyle a= 2\frac{640-8\cdot 40}{40^2}=0.4$

The acceleration is 0.4 m/s^2

(b) The final velocity is calculated by [1]:

$v_f=8+0.4\cdot 40$

$v_f=8+16=24$

The final velocity is 24 m/s

3 0

3 years ago