Answer:
The thrown rock strike 2.42 seconds earlier.
Explanation:
This is an uniformly accelerated motion problem, so in order to find the arrival time we will use the following formula:
![x=vo*t+\frac{1}{2} a*t^2\\where\\x=distance\\vo=initial velocity\\a=acceleration](https://tex.z-dn.net/?f=x%3Dvo%2At%2B%5Cfrac%7B1%7D%7B2%7D%20a%2At%5E2%5C%5Cwhere%5C%5Cx%3Ddistance%5C%5Cvo%3Dinitial%20velocity%5C%5Ca%3Dacceleration)
So now we have an equation and unkown value.
for the thrown rock
![\frac{1}{2}(9.8)*t^2+29*t-300=0](https://tex.z-dn.net/?f=%5Cfrac%7B1%7D%7B2%7D%289.8%29%2At%5E2%2B29%2At-300%3D0)
for the dropped rock
![\frac{1}{2}(9.8)*t^2+0*t-300=0](https://tex.z-dn.net/?f=%5Cfrac%7B1%7D%7B2%7D%289.8%29%2At%5E2%2B0%2At-300%3D0)
solving both equation with the quadratic formula:
![\frac{-b\±\sqrt{b^2-4*a*c} }{2*a}](https://tex.z-dn.net/?f=%5Cfrac%7B-b%5C%C2%B1%5Csqrt%7Bb%5E2-4%2Aa%2Ac%7D%20%7D%7B2%2Aa%7D)
we have:
the thrown rock arrives on t=5.4 sec
the dropped rock arrives on t=7.82 sec
so the thrown rock arrives 2.42 seconds earlier (7.82-5.4=2.42)
Answer:
Did you ever get the answer?
Explanation:
Answer:
Explanation:
According to newtons second law of motion;
F = ma .... 1
Also the force acting aong the inclines is expressed as;
F = mgsintheta
m is the mass of the object
a is the acceleration
theta is angle of inclination
Equate 1 and 2
ma = mg sin theta
a = gsin(theta)
a = 9.8sin30
a = 9.8(0.5)
a = 4.9m/s²
Hence the acceleration of the ping pong is 4.9m/s²
Answer:
Option B
Explanation:
According to quantum theory of radiation electromagnetic field or electromagnetic radiation( like light) produce by accelerated charge object and the quantum of EM radiations is photon which has discrete energy. So, EM field can have only certain values of total energy and no other value due the discrete nature of the energy of photon. Hence option B is correct