Answer:
We can conclude that there is a decrease in kinetic energy of the particles due to their elastic collision, since kinetic energy is directly proportional to squared velocity of the particles.
Explanation:
Given:
initial velocity of particle A, Ua = 5m/s
initial velocity of particle B, Ub = 10 m/s
final velocity of particle A, Va = 4m/s
final velocity of particle B, Vb = 7m/s
For particle A:
The final velocity is 1 less than the initial velocity.
For particle B:
The final velocity is 3 less than the initial velocity.
We can conclude that there is a loss in kinetic energy due to elastic collision of the two particles, since kinetic energy is directly proportional to squared velocity of the particles. A decrease in velocity means decrease in kinetic energy.
#1
Volume of lead = 100 cm^3
density of lead = 11.34 g/cm^3
mass of the lead piece = density * volume


so its weight in air will be given as

now the buoyant force on the lead is given by


now as we know that


so by solving it we got
V = 11.22 cm^3
(ii) this volume of water will weigh same as the buoyant force so it is 0.11 N
(iii) Buoyant force = 0.11 N
(iv)since the density of lead block is more than density of water so it will sink inside the water
#2
buoyant force on the lead block is balancing the weight of it




(ii) So this volume of mercury will weigh same as buoyant force and since block is floating here inside mercury so it is same as its weight = 11.11 N
(iii) Buoyant force = 11.11 N
(iv) since the density of lead is less than the density of mercury so it will float inside mercury
#3
Yes, if object density is less than the density of liquid then it will float otherwise it will sink inside the liquid
The kinetic energy of a moving object is given by

where m is the object's mass and v its velocity.
In our problem, the initial kinetic energy is:

while the final kinetic energy is:

So, the kinetic energy lost by Lucy and her bike is
<span>θ=0.3sin(4t)
w=0.3cost(4t)(4)=1.2cost(4t)
a=-4.8sin(4t)
cos4t max will always be 1 (refer to cos graph), for same reason, sin4t will always be 0
therefore, wmax=1.2rad/s
vAmax=r*w=250*1.2=300mm/s
(may be different if your picture/radius is from a different picture)
adt=a*r=200*-4.8sin(4t)=0 (sin(4t)=0)
adn=r*w^2=200*1.2^2=288
ad= square root of adt^2+adn^2 = 288mm/s^2</span>