Answer:
linear density of the string = 4.46 × 10⁻⁴ kg/m
Explanation:
given,
mass of the string = 31.2 g
length of string = 0.7 m
linear density of the string = 
linear density of the string = 
linear density of the string = 44.57 × 10⁻³ kg/m
linear density of the string = 4.46 × 10⁻⁴ kg/m
Answer:

Explanation:
The work done on a particle by external forces is defined as:

According to Newton's second law
. Thus:

Acceleration is defined as the derivative of the speed with respect to time:

Speed is defined as the derivative of the position with respect to time:

Kinetic energy is defined as
:

Explanation:
Answer is B.
B. It has a central nucleus composed of 29 protons and 35 neutrons,surrounded by an electron cloud containing 29 electrons.
I hope it's helpful!
Answer:
=3.5 m/s
Explanation:
y = x tanθ - 1/2 g x² / (u²cos²θ )
y = 0.25 , x = 0.5, θ = 40°
.25 = .50 tan40 - .5 x 9.8x x²/ u²cos²40
.25 = .42 - 2.0875/u²
u = 3.5 m / s.