Physics - 9203 OxfordAQA

Forces And Terminal Velocity P

Muhtasari

Drop a stone off a cliff and it gets faster the whole way down. Drop a skydiver out of an aircraft and something stranger happens: after roughly half a minute she stops getting faster at all, and spends the rest of the fall at a steady 44 m/s with the ground still a long way below. Nothing has caught her and nothing has switched gravity off. The air itself has grown a force big enough to match her weight, and it did so by the simple trick of her going faster.

This lesson is about that force. You will learn why a fluid pushes back harder the quicker you move through it, why every falling object therefore has a speed limit of its own, and how to read the whole story off a velocity-time graph whose gradient dies away to nothing. Then you will use the idea in both directions: parachutes, which are built to make the speed limit as low as possible, and sharks and racing cars, which are shaped to push it as high as possible.

Malengo

  1. An object moving through a fluid experiences friction. The faster the object moves, the greater the frictional forces (drag) acting on it.
  2. An object falling through a fluid will initially accelerate due to the force of gravity and the drag forces increase as the velocity increases. Eventually the resultant force will be zero and the object will move at its terminal velocity.
  3. Parachutes are designed to increase the drag force on a parachutist so that the terminal velocity is reduced. Students should be able to draw and interpret velocity-time graphs for objects that reach terminal velocity, including a consideration of the forces acting on the object.
  4. Streamlining reduces the drag force on an object so that its maximum velocity is increased. Students should be able to describe how the streamlining of a shark (an adaptation) or a car (a design feature) reduces the drag force and the object.

Ramani ya mawazo

Mada hii imechorwa ili uone jinsi mawazo yanavyounganika.

Fungua ramani ya mawazo kwenye programu

Maelezo ya Somo

Put your hand out of the window of a moving car and you can feel the topic of this lesson pressing against your palm. At walking pace you would feel nothing at all. At 30 m/s the push is strong enough to bend your wrist back. Your hand has not changed, and neither has the air: the only thing that changed is how fast the two are moving past each other.

Dokezo Kamili la Somo Linapatikana kwenye Programu ya Green Bridge

Pata programu ya Green Bridge CBT kwenye simu au kompyuta yako kwa maktaba kamili ya IGCSE: mitihani ya miaka iliyopita, miongozo ya usahihishaji, ramani za mawazo, kadi za marudio na masomo ya sauti.

Maelezo kamili ya masomo yenye michoro
Msaidizi wa kujifunza wa AI
Mitihani ya majaribio yenye muda, husahihishwa mara umalizapo
Inapatikana kwa Android, Windows, macOS, na Linux Programu ya iOS inakuja hivi karibuni

Tathmini ya Somo

Hongera kwa kukamilisha somo la Forces And Terminal Velocity P. Sasa kwa kuwa umechunguza dhana na mawazo muhimu, ni wakati wa kuweka ujuzi wako kwa mtihani. Sehemu hii inatoa mazoezi mbalimbali maswali yaliyoundwa ili kuimarisha uelewaji wako na kukusaidia kupima ufahamu wako wa nyenzo.

Utakutana na mchanganyiko wa aina mbalimbali za maswali, ikiwemo maswali ya kuchagua jibu sahihi, maswali ya majibu mafupi, na maswali ya insha. Kila swali limebuniwa kwa umakini ili kupima vipengele tofauti vya maarifa yako na ujuzi wa kufikiri kwa makini.

Tumia sehemu hii ya tathmini kama fursa ya kuimarisha uelewa wako wa mada na kubaini maeneo yoyote ambapo unaweza kuhitaji kusoma zaidi. Usikatishwe tamaa na changamoto zozote utakazokutana nazo; badala yake, zitazame kama fursa za kukua na kuboresha.

  1. An object is falling through air at its terminal velocity. What is true about the forces on the object? A. There are no forces acting on it B. Its weight is greater than the drag C. The drag is equal in size to its weight D. The drag is greater than its weight Answer: C
  2. A submarine increases its speed through the water. What happens to the drag force acting on it? A. It increases B. It decreases C. It stays the same D. It falls to zero Answer: A
  3. A skydiver of mass 90 kg falls at her terminal velocity. The gravitational field strength is 9.8 N/kg. What is the size of the drag force acting on her? A. 0 N B. 9.2 N C. 90 N D. 882 N Answer: D
  4. A parachutist opens her parachute while falling at terminal velocity. What happens to her terminal velocity? A. It increases because the drag increases B. It decreases because the drag increases C. It decreases because her weight decreases D. It stays the same because her weight is unchanged Answer: B
  5. What is the effect of streamlining the body of a car? A. The drag increases and the maximum velocity increases B. The drag increases and the maximum velocity decreases C. The drag decreases and the maximum velocity increases D. The drag decreases and the maximum velocity decreases Answer: C

Fanyia kazi maswali haya kwenye programu

Fanyia kazi maswali haya kwenye programu

Fanya Mazoezi ya Maswali ya Majaribio

Ungependa kufanya mazoezi ya maswali ya majaribio kuhusu Forces And Terminal Velocity P? Pakua programu ya Green Bridge CBT ili kupata maswali ya majaribio na tathmini kamili za mazoezi kuhusu mada hii.

Pakua Programu Kwenye Google Playstore

Kila kitu unachohitaji ili kufaulu katika JAMB, WAEC & NECO.

Green Bridge CBT Mobile App
Msaidizi wa Gumzo wa Kujifunza wa AI Uliobinafsishwa
Maswali ya mtihani zaidi ya 200,000 ya IGCSE, JAMB, WAEC na NECO
Zaidi ya Madaftari ya Masomo 1200
Msaada Nje ya Mtandao - Jifunze Wakati Wowote, Popote Pale
Ratiba ya Daraja la Kijani
Muhtasari wa Fasihi na Maswali Yanayoweza Kutokea
Fuata Utendaji na Maendeleo Yako
Maelezo ya Kina kwa Kujifunza kwa Kina