A grapefruit has a weight on earth of 4.9 newtons.what is the grapefruit mass

8. What current flows through a 1.15 kW electric fire at a potential difference of

Vilka [71]

Answer:

I = 5[amp]

Explanation:

Electrical power is defined as the product of voltage by current.

$P=V*I$

where:

P = power = 1150 [W]

V = voltage = 230 [V]

I = current [amp]

Now replacing:

$1150=230*I\\I=1150/230\\I=5[amp]$

A 15 [amp] fuse must be used. Always the fuse must be larger than the operating current, to protect the equipment from very high currents. above 15 [amp]

4 0

3 years ago

Physics question 28 plz help me

Alexus [3.1K]

Answer:

a. I = 30 A

b. E = 1080000 J = 1080 KJ

c. ΔT = 12.86°C

d. Cost = $ 4.32

Explanation:

a.

The current in the coil is given by Ohm's Law:

$V = IR\\I = \frac{V}{R}$

where,

I = current = ?

V = Voltage = 120 V

R = Resistance = 4 Ω

Therefore,

$I = \frac{120\ V}{4 \Omega}\\$

I = 30 A

b.

The energy can be calculated as:

$E = VIt\\E = (120\ V)(30\ A)(5\ min)(\frac{60\ s}{1\ min})\\$

E = 1080000 J = 1080 KJ

c.

For the increase in the temperature of water:

$E = mC\Delta T\\$

where,

m = mass of water = 20 kg

C = specific heat of water = 4.2 KJ/kg.°C

Therefore,

$1080\ KJ = (20\ kg)(4.2\ KJ/kg.^oC)\Delta T$

ΔT = 12.86°C

d.

First, we will calculate the total energy consumed:

$E=(Power)(Time)\\E=VI(Time)\\E = (120\ V)(30\ A)(0.5\ h/d)(30\ d)\\E = 54000\ Wh\\E = 54 KWh$

Now, for the cost:

$Cost = (Unit\ Cost)(Energy)\\Cost = (\$ 0.08\KWh)(54\ KWh)$

Cost = $ 4.32

7 0

3 years ago

A vertical bar magnet is dropped through the center of a horizontal loop of wire, with its north pole leading. At the instant wh

AlladinOne [14]

Answer:

The induced current will be counterclockwise.

Explanation:

Magnetic field lines always begin on north poles and end on south poles. This means that there is an increase of magnetic field lines going into the plane of the loop. The induced current will be counterclockwise to oppose this change.

7 0

4 years ago

Read 2 more answers

2. (a). Three forces that act on a particle are given by F1 = (20 i – 36 j + 73 k) N, F2 = (-17 i

AlladinOne [14]

F3 -4 wouldn’t even be a guhd add up tbsh jus delete it

5 0

4 years ago

Do I fill this chart right? Can you please check if I am wrong or not?

luda_lava [24]

Physical properties of water:

Color: No color/colorless.

Odor: Odorless.

Taste: Tasteless.

Density: 1 g/ml.

Boiling point: 100°C.

Freezing/Melting point: 0°C.

State or phase:

Vapor: Gas.

Room temperature: Liquid.

Ice: Solid.

Hence, water is a colorless, odorless, and tasteless substance whose density is 1 g/ml. It boils at 100°C and melts at 0°C. In the vapor phase, it is in a gaseous state, at room temperature, it exists in a liquid state, and when its freezes (ice) it's in the solid state.

7 0

2 years ago