3 years ago

A light bulb has a power output of 80 W and it has been left on for 90 seconds. How much work was done?

1 answer:

3 0

7200 joules of heat and light energy was dissipated into the air. But no work was done ... no force moved through no distance.

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If a photon has a frequency of 5.20 × 1014 hertz, what is the energy of the photon? Given: Planck's constant is 6.63 × 10-34 jou

Virty [35]

Answer:
E=h.f

=5.2×1014×6.63×10^-34

E=3.496×10^-30 J

4 0

3 years ago

Compare the time period of two simple pendulums of length 4m and 16m at a place.

Vlad1618 [11]

Answer:

the period of the 16 m pendulum is twice the period of the 4 m pendulum

Explanation:

Recall that the period (T) of a pendulum of length (L) is defined as:

$T=2\,\pi\,\sqrt{ \frac{L}{g} }$

where "g" is the local acceleration of gravity.

SInce both pendulums are at the same place, "g" is the same for both, and when we compare the two periods, we get:

$T_1=2\,\pi\,\sqrt{\frac{4}{g} } \\T_2=2\,\pi\,\sqrt{\frac{16}{g} } \\ \\\frac{T_2}{T_1} =\sqrt{\frac{16}{4} } =2$

therefore the period of the 16 m pendulum is twice the period of the 4 m pendulum.

5 0

3 years ago

Approximately how much energy is contained in 1 g of matter?

aleksley [76]

Option (B) is correct.Energy contained in one gram of matter=9 x 10¹³ J

Explanation:

mass= 1 g= 0.001 kg

c= velocity of light= 3 x 10⁸ m/s

The mass energy equivalence equation is given by

E = m C²

E= (0.001)(3 x 10⁸)²

E=9 x 10¹³ J

Thus energy contained in one gram of matter=9 x 10¹³ J

7 0

3 years ago

The rate of motion of a lithospheric plate with respect to a stationary location inside Earth is termed __________ plate velocit

AlekseyPX

Answer:

1. Absolute plate velocity.

2. Relative plate velocity.

Explanation:

7 0

3 years ago

This i relatively easy but still, i attached a picture

bogdanovich [222]

Ultraviolet has a shorter wavelength than microwaves, so purple also has a shorter wavelength than red.

C is thus the answer

3 0

3 years ago