Answer:
d) the amount of work is the same whether the bag is moved all at once or in two stages, provided the total height lifted is the same in either case.
Explanation:
While moving the bag to the shelf in one shot we can say that the total work done is given as
here we know that
2H = total height raised by the bag
now when we raise the bag to first shelf and then move it to next shelf
then we will have
so the correct answer will be
d) the amount of work is the same whether the bag is moved all at once or in two stages, provided the total height lifted is the same in either case.
Answer:
the rate of change in volume with time is 280πr² cm³/min
Explanation:
Data provided in the question:
Radius of the sphere as 'r'
= 70 cm/min
Volume of the sphere, V =
Surface area of the sphere as 4πr²
Now,
Rate of change in volume with time,
=
=
Substituting the value of
=
= 280πr² cm³/min
Hence, the rate of change in volume with time is 280πr² cm³/min
Answer:
a) Knowns, initial speed , final speed
and gravity due it is a constant
b) The maximum high reached by the dolphin is
c) Total time is
Explanation:
a) First of all the initial speed is given at the start of the problem, gravity is constant and final speed is known any object thrown straight up reaches its max high at speed.
b) Second, now that we know final speed we use , as we clear for
.
Then we use
c)Third, finally we can use , as we know
when the dolphin fall into the water again and
, then we have
is a quadratic form
so we have
and
Answer:
Explanation:
Given data
Space vehicle speed=5425 km/h relative to earth
The rocket motor speed=81 km/h and mass 4m
The command has mass m
From the conservation of momentum as the system isolated
Since the motion in on direction we can drop the unit vector direction
Where M is the mass of space vehicle which equals to sum of the motors mass and command mass.
The velocity of the motor relative to the earth equals the velocity of the motor relative to command plus the velocity of the command relative to earth
Where Vmc is the velocity of motor relative to command
This yields
Substitute the given values