Answer:
I wish i saw the field shown to the right
Explanation:
Answer:
Explanation:
Radius of dee, r = 8 mm = 0.008 m
Electric field, e = 400 V/m
Magnetic field, B = 4.7 x 10^-4 T
mass of electron, m = 9.1 x 10^-31 kg
charge of electron, q = 1.6 x 10^-19 C
(a) Let v is the speed of electrons.
v = 661098.9 = 661099 m/s
(b)
e / m = 1.76 x 10^14 C / kg
(c) Let K be the kinetic energy
K = 0.5 x mv²
K = 0.5 x 9.1 x 10^-31 x 661099 x 661099
K = 1.99 x 10^-19 J
K = 1.24 eV
So, the potential difference is
V = 1.24 V
(d) if the acceleration voltage is doubled
V = 2 x 1.24 = 2.48 V
So, Kinetic energy
K = 2.48 eV
K = 2.48 x 1.6 x 10^-19 = 3.968 x 10^-19 J
Let v is the speed
K = 0.5 x mv²
3.968 x 10^-19 = 0.5 x 9.1 x 10^-31 x v²
v = 933856.5 m/s
Let the new radius is r.
r = 0.0113 m = 1.13 cm
Answer:
a)
Y0 = 0 m
Vy0 = 15 m/s
ay = -9.81 m/s^2
b) 7.71 m
c) 3.06 s
Explanation:
The knowns are that the initial vertical speed (at t = 0 s) is 15 m/s upwards. Also at that time the dolphin is coming out of the water, so its initial position is 0 m. And since we can safely assume this happens in Earth, the acceleration is the acceleration of gravity, which is 9.81 m/s^2 pointing downwards
Y(0) = 0 m
Vy(0) = 15 m/s
ay = -9.81 m/s^2 (negative because it points down)
Since acceleration is constant we can use the equation for uniformly accelerated movement:
Y(t) = Y0 + Vy0 * t + 1/2 * a * t^2
To find the highest point we do the first time derivative (this is the speed:
V(t) = Vy0 + a * t
We equate this to zero
0 = Vy0 + a * t
0 = 15 - 9.81 * t
15 = 9.81 * t
t = 0.654 s
At this time it will have a height of:
Y(0.654) = 0 + 15 * 0.654 - 1/2 * 9.81 * 0.654^2 = 7.71 m
The doplhin jumps and falls back into the water, when it falls again it position will be 0 again. So we can equate the position to zero to find how long it was in the air knowing that it started the jump at t = 0s.
0 = Y0 + Vy0 * t + 1/2 * a * t^2
0 = 0 + 15 * t - 1/2 * 9.81 t^2
0 = 15 * t - 4.9 * t^2
0 = t * (15 - 4.9 * t)
t1 = 0 This is the moment it jumped into the air
0 = 15 - 4.9 * t2
15 = 4.9 * t2
t2 = 3.06 s This is the moment when it falls again.
3.06 - 0 = 3.06 s
I think its between b or c
perimeter of a rectangle = 2(L+B)
90=2(L+B)
90/2=L+B
45=L+B
