Answer:
2.4 m/s
Explanation:
Given:
Velocity of the object moving north = 2.1 m/s
Velocity of the river moving eastward = 1.2 m/s
The resultant velocity is the vector sum of the velocities of object and river.
Since the directions of velocity of object and river are perpendicular to each other, the magnitude of the resultant velocity is obtained using Pythagoras Theorem.
The velocities are the legs of the right angled triangle and the resultant velocity is the hypotenuse.
The magnitude of the resultant velocity (R) is given as:
Therefore, the resultant velocity has a magnitude of 2.4 m/s.
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
Answer:
d = 68.18 m
Explanation:
Given that,
Initial velocity, u = 15 m/s
Finally it comes to stop, v = 0
Acceleration, a = -1.65 m/s²
Time, t = 2.5 s
We need to find the distance covered by the hayride before coming to a stop. Let d is the distance covered. Using third equation of motion to find it :
So, the hayride will cover a distance of 68.18 m.
