Answer:

Explanation:
From the question we are told that
Nucleus diameter 
a 12C nucleus
Required kinetic energy 
Generally initial speed of proton must be determined,applying the law of conservation of energy we have

where
=initial kinetic energy
=final kinetic energy
=initial electric potential
=final electric potential
mathematically

where
=distance b/w charges
=nucleus charge 
=constant
=proton charge
Generally kinetic energy is know as

Therefore
Generally equation for radius is 
Mathematically solving for radius of nucleus


Generally we can easily solving mathematically substitute into v_1









Therefore the proton must be fired out with a speed of 
Answer:
Option A
Explanation:
The Equation represents the displacement of the object which is represented by x

so,
means when time is zero so we replace t with zero in the equation,

now for v which is velocity we need to differentiate the function as the formula for velocity is rate of change of displacement over time so we derivate the equation once and get,

now for
we insert t = 0 and get

now for a which is acceleration the formula of acceleration is rate of change of velocity over time, so we differentiate the the equation of v(velocity) once or the equation of x(displacement) twice so now we get,

so Option A is your answer.
Remember derivative of a constant is always zero because a constant value has no rate of change has its a constant hence the derivative is 0
Answer:
The ability to react to a certain stimulus with a speedy and effective manner
Explanation:
Objects in free fall, disregarding terminal velocity, accelerate at 9.8(m/s)/s. so for every second it was falling, it gained 9.8m/s in speed. 9.8 * 10 = 98m/s
Answer:
a= -0.83m\s^2
Explanation:
a = v \ t
a = -25 \ 30 = -0.833 m\s^2
the object is slowing down 0.83 meter every second