4:chemical properties can only be observed when a substance changes into another substance.
5: physical properties such as color and shape are easy to observe
6: in a chemical change an altered substance forms
7: cooking or baking food will result in a chemical change
8: a melting ice cube is a physical change
9: the rusting of iron is a chemical change
10: water boiling is a scientific physical change
Answer:
x=0.154kg
Explanation:
(x*L)+(0.5kg*4200*50)+(x*4200*(-50)=0
(x*333 000J/kg*c)+(0.5kg*4200J/kg*C*(-40C))+(x*4200J/kg*C*50C)=0
Answer:
31677.2 lb
Explanation:
mass of hammer (m) = 3.7 lb
initial velocity (u) = 5.8 ft/s
final velocity (v) = 0
time (t) = 0.00068 s
acceleration due to gravity (g) 32 ft/s^{2}
force = m x ( a + g )
where
- m is the mass = 3.7 lb
- g is the acceleration due to gravity = 32 ft/s^{2}
- a is the acceleration of the hammer
from v = u + at
a = (v-u)/ t
a = (0-5.8)/0.00068 = -8529.4 ( the negative sign showa the its decelerating)
we can substitute all required values into force= m x (a+g)
force = 3.7 x (8529.4 + 32) = 31677.2 lb
Answer:
Gravitational pull
Explanation:
There are four fundamental forces in nature:
- Gravitational force: it is an attractive force exerted between all objects having mass. Its magnitude is proportional to the product of the masses and inversely proportional to the square of the distance between the objects.
- Electromagnetic force: it is the force exerted between electrically charged object. It can be either attractive ore repulsive. Its magnitude is proportional to the product of the charges and inversely proportional to the square of the distance between the objects.
- Strong nuclear force: it is the force responsible for holding protons and neutrons together in the nuclei of the atoms. It is attractive and acts only on a very short scale.
- Weak nuclear force: it is the force responsible for certain nuclear decay processes (radioactivity).
In this problem, landslides occur when certain masses of terrain are attracted towards the ground - they are attracted because of the gravitational force.
So, the correct answer is
gravitational pull
