Answer:5.17 m/s
Explanation:
Given
let u be the speed at cliff initial point
range over cliff is 1.45 m
and range of projectile is given by


u=3.77 m/s
Conserving Energy

Kinetic energy=Kinetic energy +Potential energy gained
Let v be the initial velocity





Answer:
800
cm²
Explanation:
Given parameters:
radius of the coin = 20cm
Unknown:
Surface area of the coin = ?
Solution:
A coin is made up of two faces;
Surface area = 2(πr²)
Insert the parameters and solve;
Surface area = 2(
)
Surface area = 800
cm²
Answer:
The sum of all forces for the two objects with force of friction F and tension T are:
(i) m₁a₁ = F
(ii) m₂a₂ = T - F
1) no sliding infers: a₁ = a₂= a
The two equations become:
m₂a = T - m₁a
Solving for a:
a = T / (m₁+m₂) = 2.1 m/s²
2) Using equation(i):
F = m₁a = 51.1 N
3) The maximum friction is given by:
F = μsm₁g
Using equation(i) to find a₁ = a₂ = a:
a₁ = μs*g
Using equation(ii)
T = m₁μsg + m₂μsg = (m₁ + m₂)μsg = 851.6 N
4) The kinetic friction is given by: F = μkm₁g
Using equation (i) and the kinetic friction:
a₁ = μkg = 6.1 m/s²
5) Using equation(ii) and the kinetic friction:
m₂a₂ = T - μkm₁g
a₂ = (T - μkm₁g)/m₂ = 12.1 m/s²
The electric force acting on the charge is given by the charge multiplied by the electric field intensity:

where in our problem

and

, so the force is

The initial kinetic energy of the particle is zero (because it is at rest), so its final kinetic energy corresponds to the work done by the electric force for a distance of x=4 m: