Which type of hearing problem can be reduced which ordinary hearing aids

A lamp is 10% efficient.How much electrical energy must be supplied to the lamp each second if it produces 20 J of light energy

k0ka [10]

If it produces 20J of light energy in a second, then that 20J is the 10% of the supply that becomes useful output.

20 J/s = 10% of Supply

20 J/s = (0.1) x (Supply)

Divide each side by 0.1:

Supply = (20 J/s) / (0.1)

<em>Supply = 200 J/s </em>(200 watts)

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Here's something to think about: What could you do to make the lamp more efficient ? Answer: Use it for a heater !

If you use it for a heater, then the HEAT is the 'useful' part, and the light is the part that you really don't care about. Suddenly ... bada-boom ... the lamp is 90% efficient !

6 0

3 years ago

How is frame motion used to measure motion

Mice21 [21]

Answer:

To describe motion accurately and completely, a frame of reference is necessary. frame of reference ( or reference frame) consists of an abstract coordinate system and the set of physical reference points that uniquely fix ( locate and orient ) the coordinate system and standardize measurements within that frame.

Explanation:

The different observations occur because the two observers are in different frames of reference. A frame of reference is a set of coordinates that can be used to determine positions and velocities of objects in that frame; different frames of reference move relative to one another.

8 0

2 years ago

What hazard is associated with ionizing radiation?

Talja [164]

Acute health effects such as skin burns or acute radiation syndrome can occur when doses of radiation exceed certain levels.

8 0

3 years ago

Read 2 more answers

You hold your physics textbook in your hand. (Assume that no other objects are in contact with the book.)

Jet001 [13]

Answer:

1) the correct answer is b and d

2) For force b its direction is vertical up

for the force d its direction is vertical down

3) the correct answers are: a, c and d

4) Force a is vertical down , force c is vertical up and force d is vertical down

5) the correct answer which is b

Explanation:

In this exercise it is asked to identify the forces, fundamentally on the free there are the forces of gravity and the support force of the hand, with these facts we answer the questions

1) the correct answer is b and d

the hand acts on the book with a contact force and the Earth acts on the book with the force of gravity.

2) For force b its direction is vertical up

for the force d its direction is vertical down

3) The forces on the hand are the weight of the book. The force of gravity due to the mass of the hand. As the hand is in balance, there must be a force applied by the arm to keep the hand in position; assuming the hand is in the air, if the hand is resting on the floor the force of the floor on the hand can perform this function

therefore the correct answers are: a, c and d

4) Force a is vertical down

force c is vertical up

force d is vertical down

5) The action and reaction forces are forces of equal magnitude, each applied to one of the bodies, we have

* the force of the hand on the free and its reaction the force of the book on the hand

* The force of the Earth on the book and the hand, giving the weight of each one and the relationship is the force of the book and the hand on the Earth

the correct answer which is b

8 0

2 years ago

A transformer has a primary voltage of 115 V and a secondary voltage of 24 V. If the number of turns in the primary is 345, how

Eduardwww [97]

Here's a fun and useful factoid:

   The ratio of the voltages on a transformer is the same
   as the ratio of the number of turns in each winding.

So the ratio of (345 to the secondary turns) is (115V to 24V).

That's a proportion.

   (115/24) = (345/x)

I'll bet you can take it and solve it from here.
Just cross-multiply in the proportion and etc. etc.

6 0

3 years ago