Answer: a
Explanation:
when a car dives on a road it a makes friction but it need something to push it or start it which is the balloon in this example
(sorry if im wrong)
Calculate the speed of an object that travels 75m in 15s.
Answer:
5m/s
Explanation:
speed=distance/time
=75/15
=5m/s
A piece of wood that floats on water has a mass of 0.0175 kg. A lead sinker is tied to the wood, and the apparent mass with the wood in air and the lead sinker submerged in water is 0.0765 kg. The apparent mass with both the wood and the sinker both submerged in water is 0.0452 kg. What is the SG of the wood
Answer:
The specific gravity of the wood is 1.56
Explanation:
Given;
mass of the wood in water, [tex]M_w_{H_2O}[/tex] = 0.0175 kg
apparent mass of the wood and lead sinker submerged in water, [tex]M_w_{(air)} + M_s_{H_2O}[/tex] = 0.0765 kg
apparent mass with both the wood and the sinker both submerged in water, [tex]M_w_{H_2O} + M_s_{H_2O} = 0.0452 \ kg[/tex]
Mass of the lead sinker alone submerged in water;
[tex]M_w_{H_2O} + M_s_{H_2O} = 0.0452 \ kg\\\\0.0175 \ kg + M_s_{H_2O} = 0.0452 \ kg\\\\M_s_{H_2O} = 0.0452 \ kg - 0.0175 \ kg\\\\M_s_{H_2O} = 0.0277 \ kg[/tex]
Mass of the wood in the air;
[tex]M_w_{(air)} + M_s_{H_2O} = 0.0765 \ kg\\\\M_w_{(air)} + 0.0277 \ kg = 0.0765 \ kg\\\\M_w_{(air)} = 0.0765 \ kg - 0.0277 \ kg\\\\M_w_{(air)} = 0.0488 \ kg[/tex]
Mass of water is calculated as follows;
[tex]M_w_{(air)} - M_w_{H_2O} = M_{H_2O}\\\\0.0488 \ kg - 0.0175 \ kg = M_{H_2O}\\\\0.0313 \ kg = M_{H_2O}[/tex]
The specific gravity of the wood is calculated as follows;
[tex]Specific \ gravity\ (S.G) \ of \ wood = \frac{mass \ of \ wood\ in \ air }{mass \ of \ water} \\\\Specific \ gravity\ (S.G) \ of \ wood = \frac{0.0488}{0.0313} \\\\Specific \ gravity\ (S.G) \ of \ wood = 1.559 = 1.56[/tex]
Therefore, the specific gravity of the wood is 1.56
Two masses are connected by a string which passes over a pulley with negligible mass and friction. One mass hangs vertically and one mass slides on a horizontal surface. The horizontal surface has a coefficient of kinetic friction of 0.200. The vertically hanging mass is 3.00 kg and the mass on the horizontal surface is 3.00 kg. The magnitude of the acceleration of the vertically hanging mass is (the initial velocity of the horizontal mass is to the right)
Answer:
[tex]a=2,5m/s^2[/tex]
Explanation:
From the question we are told that:
Coefficient of kinetic friction [tex]\mu= 0.200[/tex]
Vertical Mass [tex]M_v=3kg[/tex]
Horizontal mass [tex]M_h=3.00kg[/tex]
Generally the equation for kinetic force [tex]F_k[/tex] is mathematically given by
[tex]F_k=\mu N\\F_k=0.2*3\\F_k=0.6[/tex]
Generally the equation for T is mathematically given by
[tex]For M_v=3kg3g-T=3a[/tex]
For [tex]M_h=3kg[/tex]
[tex]T=M_v V+F_k\\T=3.0a+0.6[/tex]
Therefore substituting
[tex]3-3a-0.6=3a\\2.4g=6a[/tex]
[tex]a=2,5m/s^2[/tex]
What is a positive effect of increased carbon dioxide within the carbon cycle?
Answer:
The positive impact in the cycle is that CO2 will make plants to use water more efficiently and also thereby make them to become drought resistant and thereby grow faster.
Explanation:
Carbon cycle is the process by which carbon dioxide travels from the atmosphere to the earth and returns back to the atmosphere.
The negative impact of carbon dioxide in the carbon cycle is that it will cause green house effect. However, when it comes to the positive impact in the cycle, CO2 will make plants to use water more efficiently and also thereby make them to become drought resistant and thereby grow faster.
Before we make measurements, let's make sure we understand the circuit. 1. Select all of the following that correctly describe what a volt meter and ammeter measure. Select all that apply: A volt meter measures the potential difference (or voltage) across a circuit element. A volt meter measures the potential difference (or voltage) passing through a circuit element. A ammeter measures the electric current passing through a circuit element. A ammeter measures the electric current across a circuit element.
Answer:
the correct answers are a and c
Explanation:
In an electrical circuit there are two important quantities to measure, such as voltage and current.
Voltage is the potential difference between two points in a circuit
current is the number of electrons you pass through a given point per unit of time.
Now let's analyze each answer
a) true. The potential difference across an element
b) False. The potential difference is u field there is no physical entity that moves
c) True. The current is electrons in motion and these pass through the given element
d) False. There is a physical quantity that passes through the point
the correct answers are a and c
A disk of a radius 50 cm rotates at a constant rate of 100 rpm. What distance in meters will a point on the outside rim travel during 30 seconds of rotation?
Answer:
the distance in meters traveled by a point outside the rim is 157.1 m
Explanation:
Given;
radius of the disk, r = 50 cm = 0.5 m
angular speed of the disk, ω = 100 rpm
time of motion, t = 30 s
The distance in meters traveled by a point outside the rim is calculated as follows;
[tex]\theta = \omega t\\\\\theta = (100 \frac{rev}{\min} \times \frac{2\pi \ rad}{1 \ rev} \times \frac{1\min}{60 s} ) \times (30 s)\\\\\theta = 100 \pi \ rad\\\\d = \theta r\\\\d = 100\pi \ \times \ 0.5m\\\\d = 50 \pi \ m = 157.1 \ m[/tex]
Therefore, the distance in meters traveled by a point outside the rim is 157.1 m
State Newton’s Universal Law of Gravitation.
Answer:
This law states that every particle attract every other particle in the universe with a force that is directly proportional to the product of their mass and inversely proportional to the square of the distance between the center
