All categories

3 years ago

Calculate the efficiency of the following appliances:

Physics

1 answer:

lubasha [3.4K]3 years ago

4 0

Answer:

1. The efficiency of the radiator is 90 %

2. The efficiency of the torch is 65 %

3. The efficiency of the car is 40 %

4. The efficiency of the energy saver is 70 %

5. The efficiency of the speaker is 50 %

Explanation:

Efficiency = (Useful energy out ÷ Total energy in) × 100 J

1. Useful energy = 900 J

The total energy in = 1000 J

The efficiency of the radiator = ((900 J)/(1,000 J)) × 100 % = 90 %

2. Useful energy = 65 J

The total energy in = 100 J

The efficiency of the torch = ((65 J)/(100 J)) × 100 % = 65 %

3. Useful energy = 4,000 J

The total energy in = 10,000 J

The efficiency of the car = ((4,000 J)/(10,000 J)) × 100 % = 40 %

4. Useful energy = 700 J

The total energy in = 1,000 J

The efficiency of the energy saver = ((700 J)/(1,000 J)) × 100 % = 70 %

5. Useful energy = 50 J

The total energy in = 100 J

The efficiency of the speaker = ((50 J)/(100 J)) × 100 % = 50 %

You might be interested in

A ping-pong ball is shot straight north from a popgun at 4.0 m/s. The wind is blowing to the west at 3.0 m/s. What is the actual

Vlad1618 [11]

Actual velocity of the ping-pong ball= 5 m/s

Explanation:

velocity of ping pong ball because of the shot gun= 4 m/s North

velocity added to the ping-pong ball due to the wind=3 m/s

These velocities are perpendicular to each other. so we use Pythagoras theorem to find the resultant velocity of the ping- pong ball

so the actual velocity of the ping-pong ball =V= √4²+3²

V= √25

V= 5 m/s

5 0

4 years ago

Can someone please help me with science.

pav-90 [236]

On the dog's return trip (between t = 10 and t = 12.5 seconds), the slope of the position function is steeper than during the first 5 seconds, which means the dog ran home faster. The only option that captures this is D.

You can check to make sure that the dog indeed runs twice as fast on the return trip. The slope of the position function during the first 5 seconds is

(change in position) / (change in time) = (5 - 0) / (5 - 0) = 5/5 = 1

while during the return trip, it is

(0 - 5) / (12.5 - 10) = -5/2.5 = -2

Ignoring the sign (which only indicates the direction in which the dog was running), we see that the dog's speed on the return trip was indeed twice as high as during the first 5 s.

8 0

3 years ago

If you are trying to get ketchup out of the bottle, the best way to do it is to turn the bottle upside down and give the bottle

Igoryamba

Answer:

Explanation:

A body remains at rest or in motion unless or until an external force is applied. This is called Law of Inertia

Now When ketchup bottle is turned upside down and smack is applied to it, it causes the ketchup to start moving thereby disturbing its motion of rest and provide its motion.

And according to the first law state of rest is broken by applying an external force.

3 0

3 years ago

Please help with this!!!!!

34kurt

(1.00 atm) (0.1156 L) = (n) (0.08206 L atm / mol K) (273 K) I hoped that helped

4 0

3 years ago

This physics problem is kinda complicated to my small brains...

Veronika [31]

Answer:

$\huge\boxed{\sf P.E. = 14700\ Joules}$

Explanation:

This work done is in the form of Potential Energy so we'll use the formula of Potential Energy.

Given Data:

Mass = m = 250 kg

Acceleration due to gravity = g = 9.8 m/s²

Height = h = 6 m

Required:

Work Done in the form of Potential Energy = P.E. = ?

Formula:

P.E. = mgh

Solution:

P.E. = (250)(9.8)(6)

P.E. = 14700 Joules

$\rule[225]{225}{2}$

Hope this helped!

4 0

3 years ago