The x component of the force is 8.4N * cos(31°) = 7.2N (2 s.f.)
From the choices given, ultraviolet rays is a type electromagnetic radiation that causes certain substances to fluoresce. It cannot be detected by the naked eye but some insects are able to see them.
Like in a fluorescent light bulb, ultraviolet or UV lights stimulates the coating of the tube to emit light.
Acceleration is defined as the rate of change of velocity, which, simply put, is a mouthful to describe how fast something speeds up, slows down, or turns. The equation for acceleration is
a = Δv / Δt,
or your final velocity - your starting velocity, then divided by the amount of time. It can also be expressed as
a = (Vf - Vi) / t,
Where Vf is your final velocity, Vi is your initial velocity, and t is the time traveled.
The question gives us that the helicopter moves from a starting velocity of 30 m/s to a final velocity of 40 m/s in the span of 5 seconds. This means we can fill in the variables to the equation, where
Vf = 40,
Vi = 30, and
t = 5.
Plug these known variables into the original equation, and we get
a = (Vf - Vi) / t = (40 - 30) / 5.
From here, the answer comes down to 10 / 5, or 2 m/s^2.
Hope this helps! If you have any questions, don't hesitate to ask :D
To solve this problem we will apply the concepts related to the Magnetic Force, which is defined as the product between the currents multiplied by the length where they are transmitted and inversely proportional to the distance that separates them, considering between them, the costs indicated below . We will simply replace the values and obtain the desired value,

Here,
= Permeability of free space
= Current at each state
= Length
= Distance of separation
Replacing with our values we have that the force is,


Therefore the magnitude of the force is 3.63N, and if the currents are in same direction then force is attractive, while if the currents are in opposite direction then force is repulsive ( force is same).
When it comes to horizontal projectiles, the formula for time is:

Where:
dy = vertical distance or height
g = acceleration due to gravity
t = time
Based on the problem, we know that the height at which the tennis ball was thrown is 78.4 m and the acceleration due to gravity is a constant 9.8m/s2. All you need to do is input that into our equation:





The time it would take is
4 seconds.