Answer: 184,615,384.6 years
Explanation:
This problem can be solve by the following equation:
(1)
Where:
is the spreading rate of the seafloor, its velocity
is the distance the Africa's west coast moved at this rate
is the time it took to the coast to move the descibed distance
Isolating from (1):
(2)
(3)
Finally:
This is the time it took to the Africa's west coastto move away from the Mid atlantic ridge.
Answer:
Explanation:
We shall apply Doppler's effect to solve the problem .
Formula for apparent frequency for a source of sound approaching an observer is as follows .
f₁ = f₀ V / (V - v )
where f₁ and f₀ are apparent and real frequency of source , V and v is velocity of sound and velocity of approaching source respectively .
Putting the given values and knowing that speed of sound is 340 m /s
f₁ =346x 340 / (340 - 39.6 )
f₁ = 391.6 Hz
In case of receding train , the formula is
f₂ = f₀ V / (V + v )
Putting the values
f₂ = 346x 340 / (340 + 39.6 )
= 309.9 Hz
Change in frequency = 391.6 - 309.9
= 81.7 Hz .
Answer:
impulse acting on it
Explanation:
The impulse is defined as the product between the force applied to an object (F) and the time interval during which the force is applied (
):
We can prove that this is equal to the change in momentum of the object. In fact, change in momentum is given by:
where m is the mass and 
is the change in velocity. Multiplying and dividing by , we get
and since 
is equal to the acceleration, a, we have
And since the product (ma) is equal to the force, we have
which corresponds to the impulse.
Answer:
b) -10 m/s
Explanation:
In perfectly elastic head on collisions of identical masses, the velocities are exchanged with one another.
I attached a picture of the diagram associated with this question.
Now,
When we check the vertical components of the tension in the rope, we will find that we have two equal components acting upwards.
These two components support the weight and each of them has a value of TcosΘ
The net force acting on the body is zero.
Fnet=Force of tension acting upwards-Force due to weight acting downwards
0 = 2TcosΘ -W
W = 2TcosΘ
T = W / 2cosΘ
