Answer:
Time= t= 1.67 secs
Explanation:
Time= t=?= 1.67 secs
Initial Velocity= Vi = 2m/s
Final Velocity= Vf = 4m/s
Average Acceleration= av= Vf-Vi/t
Putting the values : 1.2m/s²= 4-2/t
Rearranging: t= 2/1.2= 1.67 secs
Answer:
17m/s
Step by step explanation:
Using g= 10m/s²
Maximum H = (u²sin²theta) /2g
12 = u² sin²(45)/2(10)
12 = u²(0.72)/20
0.72 u²= 240
u² = 240/0.72 = 333.33
Initial velocity = 18.3m/s
Answer:
In physics, the concept of a frame of reference is used to specify the perspective from which an object or event is observed.
A frame of reference is where the measurements or observations will be made. Because of this, observing an event may be different when changing from one frame of reference to another, because the measurements will be different.
Defining frames of reference is necessary because the movement is relative, it may be that from our perspective or from a frame of reference on earth we are at rest, but seen from a frame of reference in space, we are in motion due that the earth is always moving.
Another example of frames of reference is a moving plane. Seen from the ground an object in the plane moves at the speed at which the plane travels, but if the frame of reference is fixed on the plane, the object is at rest.
Force = (mass) x (acceleration)
= (275kg) x (-4.5 m/s²) = -1,237.5 newtons.
In order for this mass to experience acceleration of -4.5 m/s²,
it must be pushed by -1,237.5 newtons of force, otherwise
it will not have that acceleration.
The plus and minus signs are completely your choice. The
positive direction is the direction you decided to call positive
when you started working with the problem. Chances are,
you probably called the positive direction the one in which
the object is already moving. That makes the acceleration
positive if the object is speeding up, negative if it's slowing
down.
If the acceleration is positive (speeding up), that means the
object is being pushed by a force in the same direction it's
already moving. If the acceleration is negative (slowing down),
that means the object is being pushed by a force opposite to
the direction it's already moving ... the negative direction.
Answer:
Boron 11
Explanation:
This element is Boron because it has 5 protons.
The isotope is Boron - 11 because it has 5 protons and 6 neutrons, 6+5=11.