The answer is 24N. Since the body is moving with constant velocity all the forces must balance (equal & opposite)
Part a)
per day electricity power consumed when 100 W bulb is used for 8 hours

for one year consumption

now the cost will be given

now when other energy efficient light is used

for one year consumption

now the cost will be given

Work = (force) x (distance) =
(200 N) x (3.5 m) = <em>700 joules</em>
Answer:
B = 191.26 cm
θ = -14.73°
Explanation:
given,
magnitude of the first displacement(A) = 146 cm
at an angle of 124°
resultant magnitude = 137 cm
and angle made with x-axis by the resultant(R) = 32.0°
component of A in X and Y direction
A x = A cos θ = 146 cos 120° = -73 cm
A y = A sin θ = 146 sin 120° = 126.4 cm
now component of resultant in x and y direction
R x = 137 cos 35°
= 112.2 cm
R y = 137 sin 35°
= 78.6 cm
resultant is the sum of two vectors
R = A + B
R x = A x + B x
B x = 112.2 - (-73) = 185.2 cm
B y = R y - A y
B y = 78.6 - 126.4 = -47.8 cm
magnitude of B
B = 
B = 
B = 191.26 cm
angle
θ = -14.73°
Metal detectors work by transmitting an electromagnetic field from the search coil into the ground. Any metal objects (targets) within the electromagnetic field will become energised and retransmit an electromagnetic field of their own.