We know that a=vf_vi/t equals equation "a" . Where a is the acceleration of the body , vf is the final velocity , vi is the initial velocity and t is equal to time . Since vi equals o m/s , vf equals to 60 m/s and t equals 10 s. Put in equation "a". a=60-0/10 =6m/s2
Answer:
29 seconds
Explanation:
First we have a constant speed of 12 m/s and the distance of 240 m, so to find the time we can use the formula:
distance = speed * time
240 = 12 * time1
time1 = 20 seconds
Then, the speed decreases at 2 m/s2 until it reaches 2 m/s. So to find this time, we use this formula:
Final speed = inicial speed + acceleration * time
2 = 12 - 2 * time2
2*time2 = 10
time2 = 5 seconds.
Then, the speed increases from 2 m/s to 22 m/s with an acceleration of 5 m/s2, so we have:
Final speed = inicial speed + acceleration * time
22 = 2 + 5 * time3
5*time3= 20
time3 = 4 seconds
The total time is:
Total time = time1 + time2 + time3 = 20 + 5 + 4 = 29 seconds
Answer:
<h2> r=mv/Be</h2>
Explanation:
If a positive charge enters a magnetic field at 90 degrees the charge is deflected in a circular path by a force that acts perpendicular to it in line with Flemings right-hand rule
to derive the radius of the path of the charge we apply
F= mv^2/r=Bev
where
m= mass of the electronic charge
e=charge
B=magnetic field
v=average speed
r=radius
rearranging we have
r=mv^2/Bev
r=mv/Be
I think that from the answers above the answer is B.