Answer:
Vx= 11.0865(m/s)
Vy= 6.4008(m/s)
Explanation:
Taking into account that 1m is equal to 0.3048 ft, the takeoff speed in m / s will be:
V= 42(ft/s) × 0.3048(m/ft) = 12.8016(m/s)
The take-off angle is equal to 30 °, taking into account the Pythagorean theorem the velocity on the X axis will be:
Vx= 12.8016 (m/s) × cos(30°)= 11.0865(m/s)
And for the same theorem the speed on the Y axis will be:
Vy= 12.8016 (m/s) × sen(30°)= 6.4008(m/s)
Answer:
b. v = 0, a = 9.8 m/s² down.
Explanation:
Hi there!
The acceleration of gravity is always directed to the ground (down) and, near the surface of the earth, has a constant value of 9.8 m/s². Since the answer "b" is the only option with an acceleration of 9.8 m/s² directed downwards, that would solve the exercise. But why is the velocity zero at the highest point?
Let´s take a look at the height function:
h(t) = h0 + v0 · t + 1/2 g · t²
Where
h0 = initial height
v0 = initial velocity
t = time
g = acceleration due to gravity
Notice that the function is a negative parabola if we consider downward as negative (in that case "g" would be negative). Then, the function has a maximum (the highest point) at the vertex of the parabola. At the maximum point, the slope of the tangent line to the function is zero, because the tangent line is horizontal at a maximum point. The slope of the tangent line to the function is the rate of change of height with respect to time, i.e, the velocity. Then, the velocity is zero at the maximum height.
Another way to see it (without calculus):
When the ball is going up, the velocity vector points up and the velocity is positive. After reaching the maximum height, the velocity vector points down and is negative (the ball starts to fall). At the maximum height, the velocity vector changed its direction from positive to negative, then at that point, the velocity vector has to be zero.
Answer:
The relationship between the wave's amplitude and frequency is such that it is inversely proportional to the frequency. The amplitude decreases as the frequency increases. The amplitude increases as the frequency decreases. The higher the energy of a wave, the higher the amplitude. The lower the energy, the lower the amplitude. Energy has no effect on wavelength, speed, or frequency, only the amplitude.
Explanation:
Answer:
The factors that affect are depth of the fluid and its density
Answer:
66.4 N
Explanation:
From Newton's second law, <em>F </em>=<em> ma</em>
where <em>F</em> is the force, <em>m</em> is the mass and <em>a</em> is the acceleration.
Because the object has acceleration in two directions and the mass is constant, the force will be in two directions. The component of the forces are:
The magnitude of the resultant force is given by
