Answer:
r = 0.0548 m
Explanation:
Given that,
Singly charged uranium-238 ions are accelerated through a potential difference of 2.20 kV and enter a uniform magnetic field of 1.90 T directed perpendicular to their velocities.
We need to find the radius of their circular path. The formula for the radius of path is given by :

m is mass of Singly charged uranium-238 ion, 
q is charge
So,

So, the radius of their circular path is equal to 0.0548 m.
 
        
             
        
        
        
U=6.9ms-¹
a=0.62ms-² 
t=3.4s
V=?
using 
v=u+at 
v=6.9+(0.62×3.4)
v= 6.9+2.108
v=9.008ms-¹
        
             
        
        
        
Answer:
The answer is below
Explanation:
The average resistivity of the human body (apart from surface resistance of the skin) is about 5.0 Ωm. The conducting path between the right and left hands can be approximated as cylinder 1.6 m long and 0.10 m in diameter. The skin resistance can be made negligible by soaking the hands in salt water. (a) What is the resistance between the hands if the skin resistance is negligible? (b) if skin resistance is negligible, what potential difference between the hands is needed for lethal shock current 100 mA? 
Solution:
The resistance (R) of a material is given by the formula:
R = ρL / A
where L is the length of the conductor, ρ is resistivity and A is the cross sectional area.
a) R = ρL / A
ρ = 5.0 Ωm, L = 1.6 m, A = π(diameter²) / 4 = π(0.1²)/4 = 0.00785 m²
R = 5(1.6) / 0.00785 = 1018.6 ohm
b) To produce 100 mA, we need to use ohms law:
I = 100 mA = 0.1 A, R = 1018.6 ohm
V = IR = 0.1(1018.6)
V = 101.86 V
 
        
             
        
        
        
The correct answer to the question is unbalanced .
EXPLANATION:
As per Newton's first laws of motion, we know that a body at rest will be at rest or a body moving with uniform velocity along a straight line will keep on moving with the same velocity along that line unless and until it is compelled by some external unbalanced forces acting on.
Hence, it is the unbalanced force which is responsible for creating the motion on the body.
As per the question, Anne applied some force on the toy car. It is called applied force. There is also frictional force between car and the surface which opposes the motion of the car. The toy car will move due to the net force acting on it. The net force is known as unbalanced force.