Answer:
she must increase the current by factor of 7
Explanation:
The magnetic field produced by a steady current flowing in a very long straight wire encircles the wire.In order to solve the question, we use this formula,
B= μo I/(2πr)
where,
'μo' represents permeability of free space i.e 4π*10-7 N/A2
B=magnetic field
I= current
r=radius
->When r= 1cm=> 0.01m
B1 = μo 
/(2π x 0.01)
->when r=7cm =>0.07m
B2 = μo 
/(2π x 0.07)
Now equating both of the magnetic fields, we have
B1= B2
μo /(2π x 0.01)= μo /(2π x 0.07)
/ = 0.01/0.07
/ = 1/ 7
Therefore, she must increase the current by factor of 7
Nicholas Copernicus correctly assumed that the planets revolved around the sun but he incorrectly assumed that the planets followed a perfect circle orbit around the sun. It was later on discovered by Johannes Kepler that the planets moved around the sun following an elliptical orbit.
Answer:
0.2 m/s
Explanation:
given,
mass of astronaut, M = 85 Kg
mass of hammer, m = 1 Kg
velocity of hammer , v =17 m/s
speed of astronaut, v' = ?
initial speed of the astronaut and the hammer be equal to zero = ?
Using conservation of momentum
(M + m) V = M v' + m v
(M + m) x 0 = 85 x v' + 1 x 17
85 v' = -17
v' = -0.2 m/s
negative sign represent the astronaut is moving in opposite direction of hammer.
Hence, the speed of the astronaut is equal to 0.2 m/s
Answer:
they will move away from each other
