Answer:
The speed of ejection is 
Solution:
As per the question:
Magnetic field density, B = 0.4 T
Density of the material in the sunspot, 
Now,
To calculate the speed of ejection of the material, v:
The magnetic field energy density is given by:

This energy density equals the kinetic energy supplied by the field.
Thus


where
m = mass of the sunspot in
= 


Answer: A) 
Explanation:
The equation for the moment of inertia
of a sphere is:
(1)
Where:
is the moment of inertia of the planet (assumed with the shape of a sphere)
is the mass of the planet
is the radius of the planet
Isolating
from (1):
(2)
Solving:
(3)
Finally:
Therefore, the correct option is A.
Answer:
The acceleration of the cheetahs is 10.1 m/s²
Explanation:
Hi there!
The equation of velocity of an object moving along a straight line with constant acceleration is the following:
v = v0 + a · t
Where:
v = velocity of the object at time t.
v0 = initial velocity.
a = acceleration.
t = time
We know that at t = 2.22 s, v = 50.0 mi/h. The initial velocity, v0, is zero.
Let's convert mi/h into m/s:
50.0 mi/h · (1609.3 m / 1 mi) · (1 h / 3600 s) = 22.4 m/s
Then, using the equation:
v = v0 + a · t
22.4 m/s = 0 m/s + a · 2.22 s
Solving for a:
22.4 m/s / 2.22 s = a
a = 10.1 m/s²
The acceleration of the cheetahs is 10.1 m/s²
Answer:
45km/hr
Explanation:
Total distance=450km
Total speed=50km/hr
Total time= distance/speed
=450/50
=9hrs
distance a=180km
speed a=60km/hr
Time a=180/60
=3hrs
Distance b=450-180=270km
Speed b=?
Time b=270/speed b
Total time=time a + time b
9=3+(270/speed b)
270/speed b =9-3
270/speed b =6
6*speed b =270
Speed b=270/6
Speed b=45km/hr