Kinetic energy = (1/2) (mass) x (speed)²
At 7.5 m/s, the object's KE is (1/2) (7.5) (7.5)² = 210.9375 joules
At 11.5 m/s, the object's KE is (1/2) (7.5) (11.5)² = 495.9375 joules
The additional energy needed to speed the object up from 7.5 m/s
to 11.5 m/s is (495.9375 - 210.9375) = <em>285 joules</em>.
That energy has to come from somewhere. Without friction, that's exactly
the amount of work that must be done to the object in order to raise its
speed by that much.
Explanation:
It is given that,
Frequency of vibration, f = 215 Hz
Amplitude, A = 0.832 mm
(a) Let T is the period of this motion. It is given by the following relation as :



(b) Speed of sound in air, v = 343 m/s
It can be given by :




Hence, this is the required solution.
Answer: from the information given, the velocity of the water will decrease but the pipe size will remain the same.
This can be proved with bernoulli's equation.
Explanation: careful analysis of the system using bernoulli's equation of flow is shown in the image attached
Answer:
the exposed core of a dead star, supported by electron degeneracy pressure.
Explanation:
A white dwarf is a low luminosity exposed core of a dead star having mass comparable to the sun but volume comparable to the earth . So its density is very high . These stars have lost the capacity to generate energy through the process of fusion . Due to high gravitational energy , it goes on shrinking but ultimately balanced by electron degeneracy pressure. It is not a main sequence star as it has lost the power of fusion .
Answer:
42.96 km/s
Explanation:
From the conservation of Energy

Mass gets cancelled

= Escape velocity of Earth = 11.2 km/s
= Velocity of projectile = 44.4 km/s

The velocity of the spacecraft when it is more than halfway to the star is 42.96 km/s