All categories

3 years ago

Question#7:a) A television uses 1500J of electric energy to produce 1100J 1 point

Physics

1 answer:

Vesnalui [34]3 years ago

4 0

Answer:

a.73.3%

b.26.6%

Explanation:

a. The efficiency is the energy output, divided by the energy input, and expressed as a percentage.

#Given the energy input as 1500J and the subsequent output as 1100J, the TV's efficiency is calculated as:

$\eta=\frac{E_o}{E_i}\\\\=\frac{1100}{1500}\times 100\%\\\\=73.33\%$

Hence, the TV has an efficiency of 33.3%

b. From a above, we know that the TV has an output of 1100J and input of 1500J.

-We therefore calculate it's wastage as the difference between output and input:

Wastage=Energy Input-Energy Output=1500J-1400J=400J

$E_w=\frac{E_{wasted}}{E_i}\times 100\%\\\\=(400/1500)\times100\%\\\\=26.67\%$

Hence, the TV has wasted of 26.6%

You might be interested in

Filament bulbs give off lots of __________ that transfers wasted energy to the surroundings. What word completes the sentence?

Anika [276]

Answer:

filament bulbs give off lots of metal filament that transfers wasted energy to the surrounding.

6 0

3 years ago

A baseball pitcher throws a baseball horizontally at a linear speed of 49.4 m/s. Before being caught, the baseball travels a hor

RideAnS [48]

Answer:

$v = 3.61 m/s$

Explanation:

As we know that ball travels horizontal distance of 24.7 m with uniform speed 49.4 m/s

so we will have

$t = \frac{x}{v_x}$

$t = \frac{24.7}{49.4}$

$t = 0.5 s$

now in the same time ball is turned by angle

$\theta = 52.7 rad$

now we know that

$\theta = \omega t$

$52.7 = \omega (0.5)$

$\omega = 105.4 rad/s$

now the tangential speed of a point at equator is given as

$v = r\omega$

$v = 0.0343(105.4)$

$v = 3.61 m/s$

4 0

4 years ago

If an automobile had a 100%-efficient engine, transferring all of the fuel's energy to work, would the engine be warm to your to

svetlana [45]

Answer:

The engine would be warm to touch, and the exhaust gases would be at ambient temperature. The engine would not vibrate nor make any noise. None of the fuel entering the engine would go unused.

Explanation:

In this ideal engine, none of these events would happen due to the nature of the efficiency.

We can define efficiency as the ratio between the used energy and the potential generable energy in the fuel.

n=W, total/(E, available).

However, in real engines the energy generated in the combustion of the fuel transforms into heat (which heates the exhost gases, and the engine therefore transfering some of this heat to the environment). Also, there are some mechanical energy loss due to vibrations and sound, which are also energy that comes from the fuel combustion.

5 0

3 years ago

How do you find acceleration due to gravity with time and height given?

Feliz [49]

Here, height is given which will be the distance for a freely falling object.

The velocity will be

$v=\text{ }\frac{h}{t}$

and the acceleration will be

$a=\frac{v}{t}$

In this way, the formula works.

3 0

1 year ago

Two blocks of masses 3 kg and 5 kg approach each other with initial velocities 4 m/s and -6 m/s respectively. The two blocks col

Kipish [7]

Answer:

Explanation:

After the collision velocity of the particle is (4î - 3ĵ)m/s . ... A particle of mass 1 kg moving with a velocity of (4i^−3j^)m/s collides with a fixed surface. ... Perfectly inelastic. D ... The common velocity of the blocks after collision is: ... A ball falls from a height of 5 m and strikes the roof of a lift. ... Stay upto date with our Newsletter! i know this is not right but just here for points see ya loser

6 0

3 years ago