Distance (m)

A hot iron horseshoe (mass = 0.35 kg ), just forged, is dropped into 1.40 L of water in a 0.45 kg iron pot initially at 22.0°C.

olga_2 [115]

Answer:

$420$ °C

Explanation:

$m_{h}$ = mass of the horseshoe = 0.35 kg

$m_{w}$ = mass of the water = 1.40 L = 1.40 kg

$m_{i}$ = mass of the iron pot = 0.45 kg

$c_{i}$ = specific heat of iron = 450 J kg⁻¹ °C⁻¹

$c_{w}$ = specific heat of water = 4186 J kg⁻¹ °C⁻¹

$T_{hi}$ = initial temperature of the horseshoe = ?

$T_{wi}$ = initial temperature of the water = 22 °C

$T_{pi}$ = initial temperature of the iron pot = 22 °C

$T_{f}$ = final temperature = 32 °C

Using conservation of Heat

$m_{h}c_{i}(T_{hi} - T_{f}) = m_{w}c_{w}(T_{f} - T_{wi}) + m_{i}c_{i}(T_{f} - T_{pi})$

$(0.35)(450)(T_{hi} - 32) = (1.40)(4186)(32 - 22) + (0.45)(450)(32 - 22)$

$(157.5)(T_{hi} - 32) = 60629$

$T_{hi} - 32 = 384.95$

$T_{hi} = 420$ °C

7 0

3 years ago

A hot-air balloon plus cargo has a mass of 308 kg and a volume of 2910 m3 on a day when the outside air density is 1.22 kg/m3. T

lesya [120]

9514 1404 393

Answer:

1.114 kg/m³

Explanation:

The total mass of the air in the balloon and the balloon + cargo will be the mass of the displaced air. If d is the density of the air in the balloon, then we have ...

2910d +308 = 2910×1.22

Solving for d, we find ...

2910d = 2919(1.22) -308

d = 1.22 -308/2910

d ≈ 1.114 . . . kg/m³

The density of the hot air is about 1.114 kg/m³.

6 0

3 years ago

The graph below shows the speed of a car as it drives along a racetrack.

nordsb [41]

Answer:

Average speed = distance/time

From 1 to 9 seconds:

Distance covered = 1 - 0.2 = 0.8 km

Time = 9 - 1 = 8 sec

Average speed = 0.8 km / 8 sec

Average speed = 0.1 km/s .

The average speed for the whole test is 1.6 km / 20 sec = 0.08 km/sec. A graph of speed vs time would average out as a horizontal line at 0.08 km/sec from 1 sec to 21 sec. The area under it would be (0.08 km/s) x (20 sec) = 1.6 km.

Surprise surprise ! The area under a speed/time graph is the distance covered during that time !

In closing, I want to express my gratitude for the gracious bounty of 3 points with which I have been showered. Moreover, the green breadcrust and tepid cloudy water have also been refreshing.

Explanation:

4 0

2 years ago

A certain parallel-plate capacitor is filled with a dielectric for which Κ = 5.5 .The area of each plate is 0.034 m2 , and the p

Nesterboy [21]

Answer:

The maximum energy that can be stored in the capacitor is 6.62 x 10⁻⁵ J

Explanation:

Given that,

dielectric constant k = 5.5

the area of each plate, A = 0.034 m²

separating distance, d = 2.0 mm = 2 x 10⁻³ m

magnitude of the electric field = 200 kN/C

Capacitance of the capacitor is calculated as follows;

$C = \frac{k \epsilon A}{d} = \frac{5.5*8.85*10^{-12}*0.034}{2*10^{-3}} = 8.275 *10^{-10} \ F$

Maximum potential difference:

V = E x d

V = 200000 x 2 x 10⁻³ = 400 V

Maximum energy that can be stored in the capacitor:

E = ¹/₂CV²

E = ¹/₂ x 8.275 x 10⁻¹⁰ x (400)²

E = 6.62 x 10⁻⁵ J

Therefore, the maximum energy that can be stored in the capacitor is 6.62 x 10⁻⁵ J

4 0

3 years ago

William Gilbert used a terella in an attempt to explain _____.

Alex787 [66]

Answer:

why compasses point towards the north and south poles of the earth.

Explanation:

hope it helps!!

6 0

2 years ago