A cylindrical container is filled with oil to a depth of 32cm. If the pressure exerted at the base of the container is known to be 2560pa then, how much is the density of the oil?

Ro = 815.5 [kg/m³]

Explanation:

We must use the following equation to find the hydrostatic pressure exerted on the bottom of the cylinder.

where:

P = pressure = 2560 [Pa]

Ro = density [kg/m³]

g = gravity acceleration = 9.81 [m/s²]

h = elevation = 32 [cm] = 0.32 [m]

the velocity you are looking for is made up of two parts: horizontally velocity, vh, and its vertical velocity, vv. the actual velocity of the ball will be these two parts added together, and because velocity is a vector then they will need to be added vectorially.  

neglecting air resistance etc etc.,  

the horizontal velocity component will be constant (because there is no accelerating force in the horizontal direction.  

vh = 8 ms-1  

the vertical velocity component has an accelerating force: 'g'.  

using v = u +at where a = g = 9.81 ms-2.  

the vertical component of velocity, vv = 0 + gt = vv =9.81 x 2  

vv = 19.62 ms-1 . the zero appears because the virtical component of velocity at time t=0 is zero. remember, the ball was thrown horizontally.  

how fast it will be moving (it actual path (being a parabola )) will be the vector sum of these two.  

adding vectorally gives: -  

v = sqr root (8^2 + 19.62^2) = sqr root(64+384.9) = 21.18 or 21.2 ms-1

float.

archimedes' principle

denser than water sinks in water.

denser than mercury would sink in it