Answer:
The correct answer is b, x = 9 cos (pi / 2 t)
Explanation:
The equation that describes a simple pendulum is
θ = θ₀ cos (wt + φ)
The angle is measured is radians
θ = x / L
We replace
d / L = x₀ / L cos (wt + φ)
x₀ = 9 in
We replace
d = 9 cos (wt + φ)
Angular velocity is related to frequency and period.
w = 2π f = 2π / T
The period is the time of a complete oscillation T = 4 s
w =2π / 4
w = π / 2
Let's replace
x = 9 cos (π/2 t + φ)
As the system is released from the root x = x₀ for t = 0 s
x₀ = x₀ cos φ
Cos φ = 1
φ = 0°
The final equation is
x = 9 cos (pi / 2 t)
The correct answer is b
Answer:
charge will be equal to
Explanation:
We have given mass of the particle m = 1.45 gram = 0.00145 kg
Acceleration due to gravity 
Electric field E = 700 N/C
Electric force will be equal to
, here q is charge and E is electric field
For particle to be stationary this force must be equal to force due to gravity , that is mg force
So qE = mg

So charge will be equal to

if currents go in opposite directions, wires repel
Answer:
The force is 
Explanation:
The moment of Inertia I is mathematically evaluated as

Substituting
for M(Mass of the wheel) and
for
(Radius of wheel)


The torque on the wheel due to net force is mathematically represented as

Substituting 135 N for
(Force acting on sprocket),
for
(radius of the chain) and F is the force acting on the sprocket due to the chain which is unknown for now

This same torque due to the net force is the also the torque that is required to rotate the wheel to have an angular acceleration of
and this torque can also be represented mathematically as

Now equating the two equation for torque
Making F the subject

Substituting values

