Explanation:
It is given that,
Relativistic Mass of the stone, m₀ = 0.6
Mass, 
Relativistic mass is given by :
.........(1)
Where
c is the speed of light
On rearranging equation (1) we get :
v = 0.61378 c
or
v = 0.6138 c
So, the correct option is (c). Hence, this is the required solution.
The car undergoes an acceleration <em>a</em> such that
(45.0 km/h)² - 0² = 2 <em>a</em> (90 m)
90 m = 0.09 km, so
(45.0 km/h)² - 0² = 2 <em>a</em> (0.09 km)
Solve for <em>a</em> :
<em>a</em> = (45.0 km/h)² / (2 (0.09 km)) = 11,250 km/h²
Ignoring friction, the net force acting on the car points in the direction of its movement (it's also pulled down by gravity, but the ground pushes back up). Newton's second law then says that the net force <em>F</em> is equal to the mass <em>m</em> times the acceleration <em>a</em>, so that
<em>F</em> = (4500 kg) (11,250 km/h²)
Recall that Newtons (N) are measured as
1 N = 1 kg • m/s²
so we should convert everything accordingly:
11,250 km/h² = (11,250 km/h²) (1000 m/km) (1/3600 h/s)² ≈ 0.868 m/s²
Then the force is
<em>F</em> = (4500 kg) (0.868 m/s²) = 3906.25 N ≈ 3900 N
Answer:
Angle = 0.2520 radians
Explanation:
Complete question:
Sound with frequency 1220Hz leaves a room through a doorway with a width of 1.13m . At what minimum angle relative to the centerline perpendicular to the doorway will someone outside the room hear no sound? Use 344m/s for the speed of sound in air and assume that the source and listener are both far enough from the doorway for Fraunhofer diffraction to apply. You can ignore effects of reflections.
Given Data:
Speed of sound =v= 344 m/sec ;
Width of doorway =d= 1.13m ;
Frequency of sound =f= 1220 Hz ;
Solution:
As we know that
Wvelength = w = v/f = 344/1220 = 0.281967m
Now we also know that
w = dsin(A) where A is the angle
A = arcsin(w/d) =14.44° = 14.44*(3.14/180) = 0.2520 radians
At the angle of 0.252 radians relative to the centreline perpendicular to the doorway a person outside the room will hear no sound under given conditions.
