Answer: Lever
Explanation: Levers are simple machines used to raise heavy loads over a short distance. It involves a beam which could be a plank, rood or metal material placed on a rigid support or pivot called the fulcrum, A Lever increases the the input force or effort applied to produce a greater output force required to move a heavy load. Levers are classed as first, second and third class Levers depending on the arrangement of the load, effort and fulcrum.
The magnitude of the electrostatic force acting on a charge q is the product between the charge and the intensity of the electric field E. The magnitude of the electron charge is

(we are not interested in the sign), so the electrostatic force magnitude is
The average velocity of Sandy is given by the total distance covered S divided by the total time taken t:

The total distance covered is

while the total time taken is 2 hours + half an hour (for the rest) + 1 hour and half, so

Therefore, the average velocity is
Answer:
Energy needed = 1100 kJ
Explanation:
Energy needed = Change in kinetic energy
Initial velocity = 15 m/s
Mass, m = 1600 kg

Final velocity = 40 m/s

Energy needed = Change in kinetic energy = 1280000-180000 = 1100000J
Energy needed = 1100 kJ
Answer:

Explanation:
Given:
- initial gauge pressure in the container,

- atmospheric pressure at sea level,

- initial volume,

- maximum pressure difference bearable by the container,

- density of the air,

- density of sea water,

<u>The relation between the change in pressure with height is given as:</u>

where:
dz = height in the atmosphere
= standard value of gravity
<em>Now putting the respective values:</em>



Is the maximum height above the ground that the container can be lifted before bursting. (<em>Since the density of air and the density of sea water are assumed to be constant.</em>)