Answer:
1. the electric potential energy of the electron when it is at the midpoint is - 2.9 x
J
2. the electric potential energy of the electron when it is 10.0 cm from the 3.00 nC charge is - 5.04 x
J
Explanation:
given information:
= 3 nC = 3 x
C
= 2 nC = 2 x
C
r = 50 cm = 0.5 m
the electric potential energy of the electron when it is at the midpoint
potential energy of the charge, F
F = k 
where
k = constant (8.99 x
)
electron charge,
= - 1.6 x
C
since it is measured at the midpoint,
r = 
= 0.25 m
thus,
F = 
= k
+ k
=
(
)
= (8.99 x
)( - 1.6 x
)(3 x
+2 x
)/0.25
= - 2.9 x
J
the electric potential energy of the electron when it is 10.0 cm from the 3.00 nC charge
= 10 cm = 0.1 m
= 0.5 - 0.1 = 0.4 m
F = k
+ k
=
(
+
)
= (8.99 x
)( - 1.6 x
)(3 x
/0.1+2 x
/0.4)
= - 5.04 x
J
Answer:252 miles
Explanation:
Given
During his way to mountain it took 7 hr to drive
and during his return trip it took 4 hr to return
Let x be the distance between home and mountain
average speed for return is 27 miles per hour faster than his former trip
let v be the speed on his way to mountain thus v+27 is his return speed
thus
----1
for return trip
-----2
divide 1 & 2




thus 
Answer:
19.1 deg
Explanation:
v = speed of the proton = 8 x 10⁶ m/s
B = magnitude of the magnetic field = 1.72 T
q = magnitude of charge on the proton = 1.6 x 10⁻¹⁹ C
F = magnitude of magnetic force on the proton = 7.20 x 10⁻¹³ N
θ = Angle between proton's velocity and magnetic field
magnitude of magnetic force on the proton is given as
F = q v B Sinθ
7.20 x 10⁻¹³ = (1.6 x 10⁻¹⁹) (8 x 10⁶) (1.72) Sinθ
Sinθ = 0.327
θ = 19.1 deg
Answer:
Time required by boat 1 for the round trip is less than that of boat 2.
Hence, boat 1 wins.
Explanation:
Case 1: Boat 1
Speed of boat = 
time = 
While going to another end
time = 
time = 
time = 1 hour
While going back,
time = 
time = 
time = 1 hour
Total time taken by boat 1 is,
Total time by boat 1 = 1 hour + 1 hour = 2 hour
Total time by boat 1 = 2 hour
Total time taken by boat 1 for the round trip is 2 hour.
Case 2: Boat 2
Speed of boat = 
time = 
While going to another end
time = 
time = 
time = 2 hour
While going back,
time = 
time = 
time = 0.66 hour
Total time taken by boat 2 is,
Total time by boat 1 = 2 hour + 0.66 hour
Total time by boat 1 = 2.66 hour
Total time taken by boat 2 for the round trip is 2.66 hour.
Time required by boat 1 for the round trip is less than that of boat 2.
Hence, boat 1 wins.