To solve this problem we will apply the concepts related to the Magnetic Force, this is given by the product between the current, the body length, the magnetic field and the angle between the force and the magnetic field, mathematically that is,

Here,
I = Current
L = Length
B = Magnetic Field
= Angle between Force and Magnetic Field
But 

Rearranging to find the Magnetic Field,

Here the force per unit length,

Replacing with our values,


Therefore the magnitude of the magnetic field in the region through which the current passes is 0.0078T
Distance = speed / time
speed = 95 m/s
time = 3 s
distance = 95 / 3 m
displacement = 95/3 m or 32 m (2 s.f.)
I believe it is A :) hope this helped
This situation describes the Hooke's Law which states that "When an elastic object - such as a spring - is stretched, the increased length is called its extension. The extension of an elastic object is directly proportional to the force applied to it". The formula is <span>F = k × e , F for the force, k for spring constant expressed in N/m, e for extension in m. This equation works for as long the spring is not stretch too much because once it exceeded its limit, the spring will not return to its original length the moment the load is removed.</span>
Specific heat capacity= heat energy/mass×temperature rise
962°C - 20°C = 942K
Heat energy (Eh) = 239 × 1.55 × 942
Eh= 348963.9J
shc of Ag: 238.6 J/kg-K
m of Ag: 1.55kg