Answer:
mb = 3.75 kg
Explanation:
System of forces in balance
ΣFx =0
ΣFy = 0
Forces acting on the box
T₁ : Tension in string 1 ,at angle of 50° with the horizontal on the left
T₂ = 40 N : Tension in string 2, at angle of 75° with the horizontal on the right.
Wb :Weightt of the box (vertical downward)
x-y T₁ and T₂ components
T₁x= T₁cos50°
T₁y= T₁sin50°
T₂x= 30*cos75° = 7.76 N
T₂y= 30*sin75° = 28.98 N
Calculation of the Wb
ΣFx = 0
T₂x-T₁x = 0
T₂x=T₁x
7.76 = T₁cos50°
T₁ = 7.76 /cos50° = 12.07 N
ΣFy = 0
T₂y+T₁y-Wb = 0
28.98 + 12.07(cos50°) = Wb
Wb = 36.74 N
Calculation of the mb ( mass of the box)
Wb = mb* g
g: acceleration due to gravity = 9.8 m/s²
mb = Wb/g
mb = 36.74 /9.8
mb = 3.75 kg
Answer:
27.1m/s
Explanation:
Given parameters:
Height of the building = 30m
Initial velocity = 12m/s
Unknown:
Final velocity = ?
Solution:
We apply one of the kinematics equation to solve this problem:
v² = u² + 2gh
v is the final velocity
u is the initial velocity
g is the acceleration due to gravity
h is the height
v² = 12² + (2 x 9.8 x 30)
v = 27.1m/s
Answer:
, charges are both positive or both negative
Explanation:
The electrostatic force between the two spheres is given by

where
k is the Coulomb's constant
q1 and q2 are the charges on the two spheres
r is the distance between the centres of the two spheres
In this problem, we have
is the force
is the distance between the spheres
because the two spheres have identical charge
Solving the formula for q, we find

And the two charges have the same sign (so, both positive or both negative), since the sign of the force is positive (+0.30 N), so it is a repulsive force.
Answer:
Explanation:
Using the equation of motion v² = u²+2as
v is the final velocity = 40m/s
u is the iniyail velocity 0m/s
a is the acceleration
s is the displacement
Substituting in the formula;
40² = 0²+2a(50)
1600 = 100a
Divide both sides by 100
100a/100 = 1600/100
a = 16
Hence the car acceleration is 16m/s²
If you give it unbalanced force it would go up and if you can't give it enough it will stay a balanced force