Answer:
v = -5 m/s
Explanation:
It is given that,
The initial velocity of the ball, u = 25 m/s
We need to find its velocity after 2 seconds in the air.
Let v is the velocity of the ball after 2 seconds. Using equation of motion to find it.
v = u + at
Here, a = -g
v = u -gt
Putting all the values,
v = 25 - (10)(3)
= 25-30
= -5 m/s
So, the velocity of the ball after 3 seconds is 5 m/s and it is in downward direction.
3 seconds (330 m) / second =
990 meter
According to Newton's Second Law of Motion, the net force experienced by the system is equal to the mass of the system in question times the acceleration in motion. In this case, the net force is the difference of gravitational force and the force experience by the motion of the airplane. This difference is already given to be 210 N.
Net force = ma
210 N = (73 kg)(a)
a = +2.92 m/s²
Thus, the acceleration of the airplane's motion is 2.92 m/s² to the positive direction which is upwards.
Answer:
Quantity of heat or heat energy
Explanation:
the quantity of heat is the calculation of the total quantity of thermal energy in an object. it's S.I unit is joules (J) and the symbol for calculating it is Q.
Answer:
The correct answer is violet, blue, green, and red emission lines.
Explanation:
When samples of pure elements are heated they emit a continuous spectrum of electromagnetic radiation. When elements are heated at very high temperatures, the electrons get excited and they jump to consequent orbits and this results in transmission of electromagnetic radiation. The four lines visible in the emission spectrum of hydrogen are violet, blue, green, and red, the most intense of which is at 656 nanometre.
