Answer:
None, if air resistance is ignored.
Explanation:
At any instant, the projectile has vertical and horizontal components of velocity.
Vertical acceleration due to gravity affects the vertical velocity by accelerating the object toward the center of the earth, and by decreasing the upward vertical velocity..
The horizontal component of velocity makes the object travel horizontally as long as the projectile is airborne.
Thsi discussion assumes that air resistance is ignored.
Answer:
L = mp*v₀*(ms*D) / (ms + mp)
Explanation:
Given info
ms = mass of the hockey stick
uis = 0 (initial speed of the hockey stick before the collision)
xis = D (initial position of center of mass of the hockey stick before the collision)
mp = mass of the puck
uip = v₀ (initial speed of the puck before the collision)
xip = 0 (initial position of center of mass of the puck before the collision)
If we apply
Ycm = (ms*xis + mp*xip) / (ms + mp)
⇒ Ycm = (ms*D + mp*0) / (ms + mp)
⇒ Ycm = (ms*D) / (ms + mp)
Now, we can apply the equation
L = m*v*R
where m = mp
v = v₀
R = Ycm
then we have
L = mp*v₀*(ms*D) / (ms + mp)
A) 750 m
First of all, let's find the wavelength of the microwave. We have
is the frequency
is the speed of light
So the wavelength of the beam is
Now we can use the formula of the single-slit diffraction to find the radius of aperture of the beam:
where
m = 1 since we are interested only in the central fringe
D = 30 km = 30,000 m
a = 2.0 m is the aperture of the antenna (which corresponds to the width of the slit)
Substituting, we find
and so, the diameter is
B) 0.23 W/m^2
First we calculate the area of the surface of the microwave at a distance of 30 km. Since the diameter of the circle is 750 m, the radius is
So the area is
And since the power is
The average intensity is
Answer:
Explanation:
a )
hear energy required to melt 1 g of ice = 340 J ,
hear energy required to melt 80 g of ice = 340 x 80 J = 27220 J .
b ) energy gained by the melted ice ( water at O°C ) = m ct
where m is mass of water , s is specific heat and t is rise in temperature
= 80 x 4.2 x ( 8°C - 0°C)
= 2688 J .
c )
energy lost by lime juice = energy gained by ice and water
= 27220 J + 2688 J .
= 29908 J .
d )
Let specific heat required be S
Heat lost by lime juice = M S T
M is mass of lime juice , S is specific heat , T is decrease in temperature
= 320 g x S x ( 29 - 8 )°C
= 6720 S
For equilibrium
Heat lost = heat gained
6720 S = 29908 J
S = 4.45 J /g °C .
