Answer and Explanation:
Before turning a hot plate on, one should consider these points:
- Check for the leads and ensure they does not trail in liquid.
- The cable should be checked for any exposed wire before turning on in order to prevent any shock.
- Any oil residue should be wiped off of the hot plate to ensure its longevity.
- It should be placed in a stable place in order to ensure safety against any hazard.
- Thus all the above mentioned points are correct to ensure safety.
Answer:
Explanation:
Force F = 20 t² N so force is variable.
friction on the crate = mgμ , μ is coefficient of kinetic friction , m is mass
Net force
= F - mgμ
= 20 t² - mgμ = m dv / dt ( Newton's 2 nd law )
m dv = (20 t² - mgμ ) dt
Integrating on both sides,
m v = 20 (t³ / 3) - mgμ t
Putting the values ,
25 x v = 20 x 4³/3 - 25 x 9.8 x .25 x 4
25 v = 426.67 - 245
25 v = 181.67
v = 7.27
v = 7.27 m /s
Answer:
G. it enables people to use pots and pans made of metal to cook food
Explanation:
Metals are known to be substances with a relative high melting point, which means that it takes a very high temperature to melt them. As used in this question, copper (Cu) and iron (Fe) at metallic elements that have high melting points.
One advantage of this property based on the options provided is that "it enables people to use pots and pans made of metal to cook food". This is because cooking food requires subjecting them to a constant temperature from a heat source e.g cooker or stove.
The material used to hold the food being cooked must possess a very high melting point to withstand the heat, hence, the importance of these metallic substances. Most pots and pans are made of steel, an alloy of iron, hence, they have high melting point.
Answer:
These planets rotate around the sun in a circular path. Likewise in a heliocentric model it is believed that the sun is at the center of the universe and the planet earth along with all other planet move around it. Thus in both geocentric model and heliocentric model bodies in space move in circular orbits.
I believe the car because it has the most mass