Answer:
Explanation:
Given
height from which ball is dropped 
and it rises to a height of 
A person caught the ball in mid-way i.e. at a height of 
from pavement
time taken to reach the bottom is given by
where y=displacement
u=initial velocity
a=acceleration
t=time
here initial velocity is zero i.e.
Similarly to reach of height 
time taken is 
The ball is caught in mid-way i.e. ball travel a distance of 
time taken is 
total time taken 
total time =3.429 s
In series combination, resister are connected end to end and current has a single path through the circuit but the potential difference varies across each resistor. Thus we can write as,
V = V1 + V2 + V3
according to Ohm's law V = IR So,
V1 = I R1, V2 = I R2, V3 = I R3
V = I R1 + I R2 + I R3
V = I(R1+R2+R3)
V =IRe
All the individual resistances become equal to the equivalent resistance.
or Re = R1 + R2 + R3......Rn
In parallel combination, each resistor'sone is connected to the positive terminal while the other end is connected to a negative terminal. The potential difference across each resistance is the same and the current passing through them is different.
V = V1 =V2=V3
I = I1+ I2+I3
Current throught each resistor will be:
I1= V/R1 , I2 = V/R2 = I3 = V/R3
I = V (1/R1+ 1/R2+1/R3)
In case of equivalent resistance I=V/Re
V/Re = V (1/R1+ 1/R2+1/R3)
So the equivalnet resistance is the sum of all resistances
1/Re = 1/R1+ 1/R2+1/R3
Answer:
Activation Energy
Explanation:
Effective collisions are those that result in a chemical reaction. In order to produce an effective collision, reactant particles must possess some minimum amount of energy. This energy, used to initiate the reaction, is called the activation energy.
d = distance the bowling ball has fallen = ?
g = acceleration due to gravity acting on the ball by earth = 9.8 m/s²
t = time of fall for the ball = 3.0 s
distance the ball has fallen is given as
d = (0.5) g t²
inserting the above values in the equation above
d = (0.5) (9.8 m/s²) (3.0 s)²
d = (0.5) (9.8 m/s²) (9.0 s²)
d = (4.9 m/s²) (9.0 s²)
d = 44.1 m
hence the distance fallen by the ball comes out to be 44.1 m
Answer:
the knee extensors must exert 15.87 N
Explanation:
Given the data in the question;
mass m = 4.5 kg
radius of gyration k = 23 cm = 0.23 m
angle ∅ = 30°
∝ = 1 rad/s²
distance of 3 cm from the axis of rotation at the knee r = 3 cm = 0.03 m
using the expression;
ζ = I∝
ζ = mk²∝
we substitute
ζ = 4.5 × (0.23)² × 1
ζ = 0.23805 N-m
so
from; ζ = rFsin∅
F = ζ / rsin∅
we substitute
F = 0.23805 / (0.03 × sin( 30 ° )
F = 0.23805 / (0.03 × 0.5)
F F = 0.23805 / 0.015
F = 15.87 N
Therefore, the knee extensors must exert 15.87 N
