Answer:
the maximum mass that can hang without sinking is 2.93 kg
Explanation:
Given: details:
sphere diameter d = 20 cm
so, radius r = 10 cm = 0.10 m
density of the Styrofoam sphere D = 300 kg/m3
sphere volume 
=4.18*10^{-3} m^3
we know that
mass M = Density * Volume
= (300)(4.18*10^{-3} m3)
=1.25 kg
mass of the water displace = volume *density of water
= 4.18*10^{-3} m3 * 1000
= 4.18 kg
The difference between the mass of water and mass of styrofoam is the amount of mass that the sphere can support
=4.18 kg -1.25 kg
= 2.93 kg
Answer:
d. the force is reduced by one quarter to 3.6 n
Explanation:
I can't particularly place what Icelandic contributed.
But every other culture contributed majorly.
So I would go for option b.
Answer:
1)a. It is constant the whole time the ball is in free-fall.
2)b. = 14 m/s
3) e. = 19.6 m/s
Explanation:
1) given that the only force acting on the ball is gravity, gravity acts along the vertical axis. Since no other force acts on the ball then the horizontal velocity will remain constant all through the flight since there is no horizontal force acting on the ball.
2) speed = distance/time
horizontal distance = 56m
Time = 4 seconds
Speed = 56m/4s = 14m/s
3) acceleration due to gravity g = 9.8m/s^2
Initial vertical velocity = u
Final vertical velocity = v = -u
Using the law of motion;
v = u + at
a = acceleration = -g = -9.8m/s^2
t = time of flight = 4
Substituting the values;
-u = u - 4(9.8)
-2u = -4(9.8)
u = -4(9.8)/-2
u = 2(9.8) = 19.6 m/s
Initial vertical velocity = u = 19.6 m/s
Answer:
Option D
Explanation:
The work done can be given by the mechanical energy used to do work, i.e., Kinetic energy and potential energy provided to do the work.
In all the cases, except option D, the energy provided to do the useful work is not zero and hence work done is not zero.
In option D, the box is being pulled with constant velocity, making the acceleration zero and thus Kinetic energy of the system is zero. Hence work done in this case is zero.
