Answer:
1.78 x 10² kg
Explanation:
KE = ½mv²
m = 2KE/v² = 2(2e4)/(54/3.6)² = 177.777...
Answer:
The power of the kettle is P = 1 watt.
Explanation:
The definition of power is:
Power equals the quotient between work and time, or:
P = w/t.
In this case, we know that the work is:
w = 1J
And the time is:
t = 1 s
Then the power will be:
P = 1J/1s = 1 J/s
Also knowing that:
1 J/s = 1 W
(w is the unit for Watt)
We can conclude that the power of the kettle is:
P = 1 W
To solve this problem we will apply the concepts related to centripetal acceleration, which will be the same - by balance - to the force of gravity on the body. To find this acceleration we must first find the orbital velocity through the Doppler formulas for the given periodic signals. In this way:
Here,
Orbital Velocity
Maximal Wavelength
Average Wavelength
c = Speed of light
Replacing with our values we have that,
<em>Note that the average signal is 3.000000m</em>
Now using the definition about centripetal acceleration we have,
Here,
v = Orbit Velocity
r = Radius of Orbit
Replacing with our values,
Applying Newton's equation for acceleration due to gravity,
Here,
G = Universal gravitational constant
M = Mass of the planet
r = Orbit
The acceleration due to gravity is the same as the previous centripetal acceleration by equilibrium, then rearranging to find the mass we have,
Therefore the mass of the planet is
Answer:
Explanation:
I assume that by "velocity" you refer to the average velocity of the man during the trip.
In that case, we have the following data:
(average velocity)
s = 0.8 km = 800 m (distance covered by the man)
Therefore, we can find the total time of the trip by using
Now, we know that the motion during this trip is a uniformly accelerated motion, so we can find the acceleration by using the suvat equation:
where
u = 0 is the initial velocity (the man starts from rest)
a is the acceleration
Using s = 800 m and t = 114.2 s, we find: