Answer:
the crown was not made of pure gold
Explanation:
Mass of gold = weight in air/ g = 7.84N/10ms-2= 0.784 Kg or 0.8Kg
From Archimedes principle:
Upthrust= weight in air- weight in a fluid
Upthrust= volume × density × g
Note density of water = 1000kgm-3
7.84-6.84= V × 1000kgm-3×10ms-2
V= 1/10000= 1×10-4 m^3
Density = mass/ volume= 0.8/1×10-4
= 8×10^3 Kgm-3
But we know the density of gold to be 19.3 ×10^3 kgm-3
Hence the crown was not made of pure gold
Answer:
-8.04 m/s2
Explanation:
To find the answer to this, you have to use the 4th kinematic equation:

You plug into the equation to get:

solve for a to get
-8.04 m/s2
football hemets have pads that are filled with air and thick foam so when they are hit the foam asorbs the hit and the air keeps the hard outer shell of the helmet from hiting the players head