Answer:
a)= 98kJ
b)=108kJ
c) = 10kJ
Explanation:
a. The work that is done by gravity on the elevator is:
Work = force * distance
= mass * gravity * distance
= 1000 * 9.81 * 10
= 98,000 J
= 98kJ
b)The net force equation in the cable
T - mg = ma
T = m(g+a)
T = 1000(9.8 + 10)
T = 10800N
The work done by the cable is
W = T × d
= 10800N × 10
= 108000
=108kJ
c) PE at 10m = 1000 * 9.81 * 10 = 98,100 J
Work done by cable = PE +KE
108,100 J = KE + 98,100 J
KE = 10,000 J
= 10kJ
=
Answer:
B
Explanation:
Atomic structure contains electrons, protons and neutrons.
Electron is very light compared to proton and neutrons.
Given that the mass of an electron is
A) equal to the mass of a proton
B) less than the mass of a neutron
C) greater than the mass of a proton
D) equal to the mass of a neutron
The correct answer is B which is less than the mass of the neurons.
Answer:
greater
Explanation:
the speed of sound in steel is greater than water. the speed of sound in wood is not, In water, the particles are much closer together, and they can quickly transmit vibration energy from one particle to the next. This means that the sound wave travels over four times faster than it would in air, but it takes a lot of energy to start the vibration.
Wood is less dense and force can make a sound.
I dont know but i know i dont lnow if this is true but the gravity is slowly going away every 4 year i dont know i think.
