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Keith_Richards [23]

4 years ago

13

A nature photographer is using a camera that has a lens with a focal length of 3.06 cm. The photographer is taking pictures of a

ncient trees in a forest and wants the lens to be focused on a very old tree that is 10.4 m away. a) How far must the lens be from the film in order for the resulting picture to be clearly focused? Answer in units of cm.

1 answer:

sleet_krkn [62]4 years ago

6 0

Answer:

film is at distance of 3.07 cm from lens

Explanation:

Given data

focal length = 3.06 cm

distance = 10.4 m = 1040 cm

to find out

How far must the lens

solution

we apply here lens formula that is

1/f = 1/p + 1/q

here f = 3.06 and p = 1040 so we find q

1/f = 1/p + 1/q

1/3.06 = 1/1040 + 1/q

1/ q = 0.3258

q = 3.0690 cm

so film is at distance of 3.07 cm from lens

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According to Ohm's Law, the potential difference (Voltage) is directly proportional to the current flowing through a conductor.

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In this case, given voltage = 60 V and current = 4 A. To find the current, first find the constant of proportionality, resistance of the heater.

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3 years ago

a 0.199 kg snowball moving west makes an inelastic collision with a 2.89 kg box moving 0.523 m/s west. afterward,they move west

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Answer:

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Explanation:

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$m_1v_1+m_2v_2=v_f(m_1+m_2)$ .

From this we solve for $v_1$ , the initial velocity of the snowball:

$\boxed{v_1=\frac{v_f(m_1+m_2)-m_2v_2}{m_1}}$

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The initial velocity of the snowball is 22.21 m/s.

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3 years ago

A woman is applying 300N/m2 of pressure on to door with her hand. Her hand has area of 0.02m2. Work out the force being applied

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3 years ago

A marathon runner completes a 42.238 km course in 2 h, 31 min, and 46 s . There is an uncertainty of 29 m in the distance run an

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Answer:

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Consider the formula for average speed $\bar{v}$ .

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The percentage uncertainty of a fraction is the sum of percentage uncertainties in

the numerator, and
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Generally, keep

two significant figures for percentage uncertainties that are less than 2%, and
one for those that are greater than 2%.

The percentage uncertainty in $\bar{v}$ here is less than 2%. Thus, keep two significant figures. However, keep more significant figures than that in calculations to make sure that the final result is accurate.

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4 years ago