Answer:
v = 15 m / s
Explanation:
In this exercise we are given the position function
x = 5 t²
and we are asked for the average velocity in an interval between t = 0 and t= 3 s, which is defined by the displacement between the time interval
let's look for the displacements
t = 0 x₀ = 0 m
t = 3 
= 5 3 2
x_{f} = 45 m
we substitute
v = 15 m / s
Answer:
The net force = 0
Explanation:
The given information includes;
The mass of the crate = 250 kg
The way the helicopter lifts the crate = Uniformly (constant rate (speed), no acceleration)
In order to pull the crate upwards, the helicopter has to provide a force equivalent to the weight of the crate keeping the helicopter on the ground.
The weight of the crate = The mass of the crate × The acceleration due gravity acting on the crate
The weight of the crate, 
↓ = 250 kg × 9.81 m/s² = 2,452.5 N
The force the helicopter should provide to just lift the crate, 
↑ = The weight of the crate = 2,452.5 N
The net force, 
= ↑ - ↓ = 2,452.5 N - 2,452.5 N = 0
The net force = 0.
Answer:
C. while the magnet is moving
Explanation:
Electromagnetic induction implies the production of electric current by mere movement of a magnet with respect to a coil or wire.
In the given question, current would be induced in the wire only when the magnet moves. That is either when the magnet is pushed into a wire, or when pulled out. But no current would flow through the wire when the magnet is left there for a while.
The current is induced because of the motion involved. Thus, the appropriate option is C.
Answer:
3. they can travel through solids
4. they move rock at right angles to the direction of wave travel
Explanation:
- S waves are called transverse waves they have the ability to move past the solids. They cannot move through the liquids, these waves are perpendicular to the direction of travel.
- They are also called longitudinal waves, the ad is second to record on the seismograph as they slowly pass through the rocks. They have a speed of 3.4 to 7.2 km as per the boundary.
<span>When two or more identical capacitors (or resistors) are connected
in series across a potential difference, the potential difference divides
equally among them.
For example, if you have nine identical capacitors (or resistors) all
connected end-to-end like elephants in a circus parade, and you
connect the string to a source of 117 volts (either AC or DC), then
you will measure
(117v / 9) = 13 volts
across each unit in the string.</span>
