robert7248
18.10.2021 •
Physics
After classes on Friday, students wanted to travel to Como on a train that leaves the Lugano station at 15:55 pm. They board the 15:36 pm bus outside the school parking lot. The Collina d’Oro was full of traffic and the bus could only travel at an average speed of 20 km/h for the 2 km to the first stoplight. The bus then had to wait at the stoplight for 1 minute. After turning the corner the bus could still only average 20 km/h for the next 4 km down to the bus stop at the back of the train station. The students knew they needed to hurry and sprinted the last 300 meters from the bus stop, under the tracks and up to the train platform at an average speed of 5 m/s. Do they make it before the train leaves at exactly its scheduled time of 15:55 pm?
Solved
Show answers
More tips
- H Health and Medicine How to Treat Styes: Causes, Symptoms, and Home Remedies...
- C Computers and Internet How to Learn to Type Fast?...
- F Food and Cooking Delight for Gourmets: How to Prepare Liver Pate...
- S Style and Beauty How to braid friendship bracelets?...
- H Health and Medicine Mercury Thermometer Danger: What to do when a thermometer breaks?...
- F Food and Cooking Which Calamari Salad is the Most Delicious?...
- S Society and Politics 10 Tips for Boosting Your Self-Esteem...
- F Food and Cooking The Most Delicious and Simple Fish in Batter Recipe...
- H Health and Medicine What is Autism? Understanding the Basics of This Neurodevelopmental Disorder...
- P Philosophy How to Develop Extrasensory Abilities?...
Answers on questions: Physics
- P Physics In the organization of living things, tissues combine to form a) cells. eliminate b) communities. c) organisms. d) organs....
- P Physics In a particular set of experimental trials, students examine a system described by the equation given below. for experimental control, in these trials all quantities except d...
- P Physics The forklift exerts a 1,500.0 n force on the box and moves it 3.00 m forward to the stack. how much work does the forklift do against the force of gravity?...
- P Physics Redox reactions involve the gain or loss of . neutronsb. phosphatec. electronsd. protons...
- P Physics 8. a bowling ball rolls 32 meters in 0.8 seconds. find the average speed (in m/s) of the bowling ball in m/s....
- P Physics The presence of karst topography is most useful in predicting nearby a) weather patterns. b) bedrock contents. c) volcanic frequency. d) earthquake frequency....
- P Physics Which dartboard represents high accuracy and low precision?...
- P Physics Help pls!! acceleration: a) the rate of change of position b) acceleration caused by the force of gravitation c) the rate of change in velocity; speeding up, slowing down, or...
- P Physics On a hot summer day, you decide to make some iced tea. First, you brew 1.50 LL of hot tea and leave it to steep until it has reached a temperature of TteaTteaT_tea = 75.0 ∘C∘C....
- P Physics A cylindrical piece of wood of height H, radius r, and uniform density rhoc is bobbing up and down in still water with its axis aligned vertically. The density of the water is...
Ответ:
0.147 J
Explanation:
The total energy that has been transformed into thermal energy is equal to the loss of gravitational potential energy between the initial situation (bob at h=0.5 m above the ground) and the final situation (bob back but at h=0.45 m above the ground).
Therefore, we have
where
m = 0.3 kg is the mass of the bob
g = 9.8 m/s^2
h1 = 0.5 m is the initial height
h2 = 0.45 m is the final height
Substituting, we find the thermal energy
Therefore, the energy transformed into thermal energy is 0.147 J.