Answer:
molecular formula = 
Explanation:
Given data
c = 92.25%
H = 7.75%
molar mass = 104 g/mol
to find out
the empirical and molecular formula for styrene
solution
we know that
styrene 1 g contain = 0.9225 g C and 0.0775 g H
so
C = 104 × 0.9225 g / 12 g/mol
C = 7.995 mol = approx 8 mol
and
H = 104 × 0.0775 g / 1 g/mol
H = 8.06 mol = approx 8 mol
so we say that 1 mole of styrene have 8 mole of C and H
so
molecular formula =
Answer:
Here,
Initial velocity(u)=0 m/s
acceleration(a)=1.5m/s
time(t)=0.5s
Now,
distance covered(s)=ut+(1/2)at^2
=0*0.5+(1/2)*1.5*0.5*0.5
=0+(1/2)*0.375
=0+0.1875
=0.1875(nearly 0.19)
Hence,0.19 is correct answer.
Answer:
47.8rad/s
Explanation:
For energy to be conserved.
The potential energy sustain by the object would be equal to K.E
P.E = m× g× h = 2 × 9.81× 3.5= 68.67J
Now K.E = 1/2 × I × (w1^2 - w0^2)
I = 2/3 × M × R2
= 2/3 × 2 × (0.23)^2= 0.0705
Hence
W1 = final angular velocity
Wo = initial angular velocity
From P.E = K.E we have;
68.67J = 1/2 × 0.0705 × (w1^2 - w0^2)
(w1^2 - w0^2) = 1948.09
W1^2 = 1948.09 + (18.3^2)
W1^2=2282.98
W1 = √2282.98
=47.78rad/s
= 47.8rad/s to 1 decimal place.
Answer:
The cart will accelerate to the left
Explanation:
The cart is initially at rest. In order to understand its motion, we should consider the net force acting on the cart. We have two forces acting on it:
- A force of 7 N to the left
- A force of 5 N to the right
Therefore, the net force is
in the direction of the stronger force (so, to the left).
According to Newton's second law:
a net force different from zero produces an acceleration of the object, in the same direction as the net force. Therefore, the cart will accelerate to the left.
Answer:
38 m/s
43 m/s
Explanation:
x = 18t + 5.0t²
The instantaneous velocity is the first derivative:
v = 18 + 10.t
At t = 2.0:
v = 18 + 10.(2.0)
v = 38 m/s
The average velocity is the change in position over change in time.
v = Δx / Δt
v = [ (18t₂ + 5.0t₂²) − (18t₁ + 5.0t₁²) ] / (t₂ − t₁)
Between t = 2.0 and t = 3.0:
v = [ (18(3.0) + 5.0(3.0)²) − (18(2.0) + 5.0(2.0)²) ] / (3.0 − 2.0)
v = [ (54 + 45) − (36 + 20.) ] / 1.0
v = 99 − 56
v = 43 m/s
