When the projectile is at its maximum height above ground, it's at the point
of changing from rising to falling. At that exact point, its vertical speed is zero,
so the 14 m/s must be all horizontal velocity. That's not going to change.
Since we need to consider changes in vertical speed now, we need to make
some assumption about where this is all happening, so that we know the
acceleration of gravity. I'll assume that it's all happening on or near the Earth,
and the acceleration of gravity is 9.8 m/s².
I'm also going to neglect air resistance.
a). 1.2 sec before it reaches its maximum height, the projectile is rising
at a vertical speed of (1.2 x 9.8) = 11.76 m/s.
The magnitude of its velocity is
the square root of (14² + 11.76²) = 18.28 m/s, directed about 40° above horizontal.
b). 1.2 sec after it reaches its maximum height, the projectile is falling
at a vertical speed of (1.2 x 9.8) = 11.76 m/s.
The magnitude of its velocity is
the square root of (14² + 11.76²) = 18.28 m/s, directed about 40° below horizontal.
===========================
In 1.2 second before or after zero vertical speed, an object in free fall moves
(1/2) (g) (t²) = (4.9) (1.2²) = 7.06 meters .
c). & d).
1.2 seconds before it reaches maximum height, the projectile is located at
x = -14 m
y = -7.06 m
e). & f).
1.2 seconds after it reaches maximum height, the projectile is located at
x = +14 m
y = -7.06 m .
I hope you recognize that 6 answers, plus a little bit of explanation,
all for 5 points, ain't too shabby. You made out well.
Answer:
2000 W
Explanation:
First of all, we need to find the output voltage in the transformer, by using the transformer equation:
where here we have
V1 = 200 V is the voltage in the primary coil
V2 is the voltage in the secondary coil
N1 = 250 is the number of turns in the primary coil
N2 = 500 is the number of turns in the secondary coil
Solving for V2,
Now we can find the power output, which is given by
P = VI
where
V = 400 V is the output voltage
I = 5 A is the output current
Substituting,
P = (400 V)(5 A) = 2,000 W
Use the inverse square law, thus if you move a distance of 3m away, the sound intensity decrease by 1/3^2= 1/9
Answer:
392 Newtons
Explanation:
In order to find the weight, you have to multiply the mass by the gravitation constant (9.8), which gives us 40.0 * 9.8 = 392 Newtons.
Answer:
8.46 N/C
Explanation:
Using Gauss law
Gauss's Law states that the electric flux through a surface is proportional to the net charge in the surface, and that the electric field E of a point charge Q at a distance r from the charge
Here, K is Coulomb's constant whose value is 
r = 0.43 + 0.106 = 0.536 m
