a water heater has a power rating of 1 kW. how many seconds will this heater take to boil 1 liter of water?

Answer:

a) 16675.75 Kg/m³ b) 77.6%

Explanation:

The weight of the crown is 60 N, with gold's density at 19300 Kg/m³, lead's at 11340 kg/m³, water's at 1000kg/m³, and gravitational acceleration at 9.8 m/s².

The upthrust acting on the crown equals the weight in air minus its weight in water: 60 - 56.4 results in 3.6 N.

This leads to the mass of water displaced being 3.6 / 9.8, as weight equals mass times gravity.

The mass of displaced water is 0.367 Kg.

The density of water relates mass to volume as: 1000 = 0.367 / volume.

Cross-multiplying helps us determine the volume:

The crown’s volume becomes 0.367 / 1000 = 0.000367 m³ since it displaces an equal volume of water per Archimedes' principle.

Let V1 denote the gold volume and V2 the lead volume.

Total volume for the crown becomes V1 + V2.

Likewise, using the relationship of densities:

Density of gold translates to mass of gold over V1 and lead density translates to mass of lead over V2.

Thus, 19300 = mass of gold in the crown / V1 and 11340 = mass of lead in the crown / V2.

Combining them gives us: 19300 V1 = mass of gold and 11340 V2 = mass of lead.

Adding together leads to: 19300 V1 + 11340 V2 = weight of the crown / 9.8.

So, 19300 V1 + 11340 V2 = 6.12.

From V1 + V2 = 0.000367, we can express V1 in relation to V2.

V1 = 0.000367 - V2.

Substituting this into the mass equation results in:

19300 (0.000367 - V2) + 11340 V2 = 6.12.

Expanding gives:

7.083 - 19300 V2 + 11340 V2 = 6.12.

Reorganizing yields:

-7960 V2 = 6.12 - 7.083.

So, -7960 V2 = -0.963.

This leads to V2 = -0.963 / -7960 = 0.000121 (the lead volume in the crown).

Substituting V2 back into the total volume equation gives:

V1 + 0.000121 = 0.000367 m³

Thus, V1 = 0.000367 - 0.000121 = 0.000246 m³ (the gold volume in the crown).

Which leads to the mass of gold in the crown = 19300 × 0.000246 = 4.748 kg.

The mass of lead equals 11340 × 0.000121 = 1.372 kg.

The average density for the crown calculates as (mass of gold + mass of lead) / total volume = 6.12 / 0.000367 = 16675.75 kg/m³.

b) The percentage of gold by weight computes to mass of gold / total mass × 100 = approximately 77.6%.

Answer:

The total energy can be expressed as

Explanation:

The problem states that

The Poynting vector, which measures energy flux, equals

The rectangle's length is represented by

The width of the rectangle is

The duration considered is

Mathematically, the overall electromagnetic energy incident on the area is given by

where A denotes the area of the rectangle, calculated as

By plugging in the respective values

Again substituting values

B. The charge on A is -q; B has no charge. Given that a positive charge is situated at the center of an uncharged metallic sphere which is insulated and disconnected from the ground, a negative charge (-q) will appear on the inner surface A of the sphere. Should the exterior surface B be grounded, it will become neutral, resulting in no charge remaining on surface B.

1 meter per second converts to 2.237 miles per hour

therefore, 83 m/sec is equal to 185.666 miles per hour!!...here is the answer!!

Answer:

A = 4.76 x 10⁻⁴ m²

Explanation:

Given data:

Person's weight = 625 N

Bike's weight = 98 N

Pressure per tire = 7.60 x 10⁵ Pa

Find: Contact area per tire

Total system weight = 625 + 98 = 723 N

Let F represent the force supported by each tire

2F = 723 N

Therefore, F = 361.5 N

Using the formula F = P × A

Contact area, A = 4.76 x 10⁻⁴ m²