Answer:
Explanation:18kt alloy contains
i) 75% of gold
rhogold=19.3g/cm^3
=75/100×19.3
=14.475g/cm^3
ii) 16% of silver
rhosilver=10.5g/cm^3
=16/100×10.5
=1.68g/cm^3
iii) 9% of copper
rhocopper =8.90g/cm^3
=9/100×8.9
=0.801g/cm^3
Overall density of 18kt gold
=(0.801+1.68+14.475)g/cm^3
=16.956g/cm^3
=17g/cm^3 to 3s.f
Answer:
1. Battery
2. Copper wire
3. Nail or piece of metal (zinc, iron, or steel).
The final velocity of the composite object is 6/5 m/sec.
<h3>
what is velocity?</h3>
- Velocity is the direction at which an item is moving and serves as a measure of the rate at which its location is changing as seen from a certain point of view and as measured by a specific unit of time (for example, 60 km/h northbound).
- In kinematics, the area of classical mechanics that deals with the motion of bodies, velocity is a basic idea.
- A physical vector quantity called velocity must have both a magnitude and a direction in order to be defined.
- Speed is the scalar absolute value (magnitude) of velocity; it is a coherent derived unit whose quantity is measured in metres per second (m/s or m/s1) in the SI (metric system).
To learn more about the topic, refer to the following link:
brainly.com/question/80295?source=archive
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-- If there are only <em>10</em> elements in the universe that can make compound molecules, and a compound molecule can be formed by combining 1, 2, 3, or 4 different elements, then that's already the possibility of at least 400 different molecules.
-- There are many more than 10 elements that can combine to form compound molecules.
-- Every single "<em>organic</em>" molecule, of which there are thousands, is the combination of <em>carbon</em> with other elements.
-- Most all of the substances that can be distilled out of oil, including the paraffin waxes, the alcohols, gasoline, kerosene, butane, propane, octane, and natural gas, are made of just carbon, hydrogen, and oxygen, only with different numbers of each one.
-- Plastics, drugs, rubber, and DNA are examples of molecules that are made of <em>hundreds</em> of atoms.
The electrical energy consumed by a toaster is 0.033 Kwh.
<u>Explanation</u>:
The power utilized by the toaster is 400 W.

The toaster is operated for 5 Minutes.

We know that,

Substitute the values in the above formula to obtain electrical energy,

Electrical energy = 0.4 × 0.083
Electrical energy is 0.033 Kwh.