Answer:
(a). The ball's centripetal acceleration is 
(b). The magnitude of the net force is 232.9 N.
Explanation:
Given that,
Mass of baseball = 144 g
Speed = 81 mph = 36.2 m/s
Distance = 81 cm
(a). We need top calculate the ball's centripetal acceleration just before it is released
Using formula of centripetal acceleration

Where, v = speed
r = radius
Put the value into the formula



(b). We need to calculate the magnitude of the net force that is acting on the ball just before it is released
Using formula of force

Put the value into the formula


Hence, (a). The ball's centripetal acceleration is 
(b). The magnitude of the net force is 232.9 N.
Answer:
H = 1/2 g t^2 where t is time to fall a height H
H = 1/8 g T^2 where T is total time in air (2 t = T)
R = V T cos θ horizontal range
3/4 g T^2 = V T cos θ 6 H = R given in problem
cos θ = 3 g T / (4 V) (I)
Now t = V sin θ / g time for projectile to fall from max height
T = 2 V sin θ / g
T / V = 2 sin θ / g
cos θ = 3 g / 4 (T / V) from (I)
cos θ = 3 g / 4 * 2 sin V / g = 6 / 4 sin θ
tan θ = 2/3
θ = 33.7 deg
As a check- let V = 100 m/s
Vx = 100 cos 33.7 = 83,2
Vy = 100 sin 33,7 = 55.5
T = 2 * 55.5 / 9.8 = 11.3 sec
H = 1/2 * 9.8 * (11.3 / 2)^2 = 156
R = 83.2 * 11.3 = 932
R / H = 932 / 156 = 5.97 6 within rounding
Explanation:
moment is an expression involving the product of a distance and physical quantities.
-the size of force applied.
-the perpendicular distance from the pivot to the line of action of the force
Answer:
The vacuum tube was replaced with transistor.
Explanation:
- The invention of semiconductor was very useful in making solid state transistor that allowed the production of small yet faster, cheaper, and more trusted and reliable computers.
- These solid state transistor is so often used that, it nearly replaced all the use of transistor.
- This replacement took place after the invention of semiconductor in the year around 1940.
- Vacuum tubes also known as thermionic tubes are not used anymore in computers and electronics.
In a series circuit, there is only one path for current to take.
If more bulbs are added, then the same current loses more energy,
making heat and light on its way through more bulbs, so the ones that
were there before become dimmer.