Answer:
All the elements of a period have similar chemical properties because they have the same number of valence electrons in their outermost shell. Their atoms have the same number of electrons in the highest occupied energy level
A spinning top is the answer
Answer:
Total energy is 170 kJ
Explanation:
Given data:
latent heat of fusion of alcohol is 25 kcal/kg
melting point of alcohol is -114 degree c
specific heat us 0.60 k cal/kg degree c
energy need for 2 kg solid alcohol is
for Melting:
Energy Q is calculated as
Energy, Q = 25 \times 2.0 kg = 50 kJ
Energy required for Heating liquid:
Energy, ΔH = 2.0 kg \times 0.60 \times (100°C) = 120 kJ
Total energy = (50 kJ + 120 kJ) = 170 kJ
Answer:
Impulse = 88 kg m/s
Mass = 8.8 kg
Explanation:
<u>We are given a graph of Force vs. Time. Looking at the graph we can see that the Force acts approximately between the time interval from 1sec to 4sec. </u>
Newton's Second Law relates an object's acceleration as a function of both the object's mass and the applied net force on the object. It is expressed as:
Eqn. (1)
where
: is the Net Force in Newtons ( 
)
: is the mass ( 
)
: is the acceleration ( 
)
We also know that the acceleration is denoted by the velocity ( 
) of an object as a function of time ( 
) with
Eqn. (2)
Now substituting Eqn. (2) into Eqn. (1) we have
Eqn. (3)
However since in Eqn. (3) the time-variable is present, as a result the left hand side (i.e. 
is in fact the Impulse 
of the cart ), whilst the right hand side denotes the change in momentum of the cart, which by definition gives as the impulse. Also from the graph we can say that the Net Force is approximately ≈ 
and 
(thus just before the cut-off time of the force acting).
Thus to find the Impulse we have:
So the impulse of the cart is 
Then, we know that the cart is moving at 
. Plugging in the values in Eqn. (3) we have:
So the mass of the cart is 
.
