Answer:
71195 seconds or 19.8 hours
Explanation:
Because the steel will be melted, beginning from room temperature, energy is needed to heat it from room temperature to 1600°C and another to melt it at 1600°C.
We take room temperature to be 27°C, the specific heat capacity of steel to be 420 J/kg/K and the specific latent heat of fusion of steel to be 440 J/kg.
The heat required to heat the steel from room temperature to 1600°C is given by
is the mass, 
is the specific heat capacity and 
is the change in temperature.
The heat required to melt it at 1600°C is
is the mass and 
is the specific latent heat of fusion of steel.
Adding both, the heat required is 
Because the oven is 65% efficient, its output power = 
Now, energy = power * time
Time = Energy/power
1) True.
Uniform circular motion means that the angular velocity
is constant, and since the centripetal acceleration is given by
if
is constant, then a is constant.
2) The correct answer is
<span>a.) the angular velocity and linear velocities are the same
The three knots are in fact on a circle, therefore the angular velocities are the same (because they cover the same angle in the same time) and the linear velocities are the same as well, because it is given by
</span>
and since both r(distance from the center) and
are the same, v is also the same.
3) <span>b.) toward the center
In fact, an object can move on a circular path only if there is a force pushing towards the center. This force is called "centripetal force".</span>
Answer:
10.29 cm/s
Explanation:
Discharge in to the bowl = 17.0 cm³/s
Diameter of the bowl, d₁ = 1.45 cm
Now,
Rate at which water level rise at its diameter = 
also,
Area of cross-section = 
or
Area of cross-section = 1.651 cm²
Therefore,
Rate at which water level rise at its diameter = 
or
Rate at which water level rise at its diameter = 10.29 cm/s
Time taken for a message to sent from earth to reach the first astronauts is 140 second.
It takes about three days for a spacecraft to reach the Moon. in the course of that time a spacecraft travels at the least 240,000 miles 386,400 km that is the space between Earth and the Moon. The specific distance depends at the specific path selected.
The distance from earth to moon is approximately3.84*108m
So, the distance from earth to the astronauts is3.84*108m - 10500*103m =3.735*108m
The speed of light c = 2.99792458*108m/s
So, divided the distance from earth to astronauts by the speed off light,
3.735*108m/2.99792458*108m/s ˜1.25seconds
Divided the Pluto-earth distance by speed of light:
Hence, 4.2*1010m/2.99792458*108m/s = 140seconds
Learn more about astronauts here:-brainly.com/question/24496270
#SPJ4
Newton's first law of motion is connected with inertia :)
