Sue from Burkey and Keith from Baron will meet in 2 minutes
Answer: Option b
<u>Explanation:</u>
Time taken can be calculated when distance and the speeds are given. Here speeds of Keith and Sue are given. So, we have to find the relative speeds in order to calculate the time taken.
When two objects travel in same direction the relative speed will be the difference between speeds. Similarly when two objects travel in opposite direction, the relative speed will be the sum of given speeds.
Given:
Speed of Sue from Burkey is 6 km/hr and speed of Keith from Baron is 3 km/hr.
The distance between Burkey and Baron is 300 m.
From the formula,
where d is distance,s is speed and t is time
It can be derived that,
s = sum of given speeds = 3 km/hr + 6 km/hr = 9 km/hr
d = 300 m = 0.3 km
Answer:
a, b) part a and b on diagram attached
c) sf = -35 i + 20 j
35 km West and 20 km North
Explanation:
For part a and b refer to the attached co-ordinate system:
Note: unit vector i is in West/East direction and unit vector j is in North/South direction.
si = -15 i + 25 j
sf-si = -20 i - 5 j
Hence,
Mark relative position from habitat sf = si + sf/i
sf = ( -15 i + 25 j ) + ( -20 i - 5 j )
sf = -35 i + 20 j
35 km West and 20 km North
Answer:
Approximately (given that the magnitude of this charge is
.)
Explanation:
If a charge of magnitude is placed in an electric field of magnitude
, the magnitude of the electrostatic force on that charge would be
.
The magnitude of this charge is . Apply the unit conversion
:
.
An electric field of magnitude would exert on this charge a force with a magnitude of:
.
Note that the electric charge in this question is negative. Hence, electrostatic force on this charge would be opposite in direction to the the electric field. Since the electric field points due south, the electrostatic force on this charge would point due north.