Answer:
lower
Explanation:
The lower the value of the coefficient of friction, the lower the resistance to sliding.
The coefficient of friction is the ratio of the frictional force and the normal force pressing two surfaces in contact together.
U = 
U is the coefficient of friction
F is the frictional force
N is the normal force
We see that coefficient of friction is directly proportional to frictional force.
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
C.) a magnetic field is the correct answer…
<span>they are travelling at right angles to each other.
At any given instant they form a right triangle with their starting point
</span>South bound <span>= x [mi/h]
</span> East bound <span> = x+1 [mi/h]
after five hours they will be
d=5x
and
d=5(x+1)
miles away from the starting point
(5x)^2+(5(x+1))^2=625
25x^2+(5x+5)^2=625
25x^2+25x^2+50x+25=625
50</span>x^2+50x-600=0
<span> x^2+ x - 12=0
(x+4)(x-3)=0
take the postive value
x= 3 mph the speed of south bound
4mph east bound </span>
Answer
given,
length of slender rod =80 cm = 0.8 m
mass of rod = 0.39 Kg
mass of small sphere = 0.0200 kg
mass of another sphere weld = 0.0500 Kg
calculating the moment of inertia of the system
using conservation of energy
we know,
v = r ω
v = 1.084 m/s
