{"questions":[{"id":"matric-phy10-shm-01","v":1,"subject":"physics-10","chapter":"simple-harmonic-motion-and-waves","seed":true,"difficulty":1,"stem":"The time period of a simple pendulum depends on:","options":["The mass of the bob","The amplitude (for small swings)","The length of the pendulum","The material of the string"],"answer":2,"explain":{"en":"For small swings, T = 2π√(l/g): the period depends only on the length l and the acceleration due to gravity g, not on the mass of the bob or the amplitude.","ur":"چھوٹے جھولوں کے لیے T = 2π√(l/g): دورانیہ صرف لمبائی l اور ثقلی اسراع g پر منحصر ہے، گولے کے ماس یا ایمپلیٹیوڈ پر نہیں۔"},"source":{"kind":"parcha-original"},"status":"sample","exam":"matric"},{"id":"matric-phy10-shm-02","v":1,"subject":"physics-10","chapter":"simple-harmonic-motion-and-waves","difficulty":1,"stem":"The SI unit of frequency is the:","options":["Hertz","Second","Metre","Newton"],"answer":0,"explain":{"en":"Frequency is the number of vibrations per second; 1 hertz (Hz) = 1 vibration per second = 1 s⁻¹. The second is the unit of the time period.","ur":"فریکوئنسی فی سیکنڈ ارتعاشات کی تعداد ہے؛ 1 ہرٹز (Hz) = ایک ارتعاش فی سیکنڈ۔ سیکنڈ دورانیے کی اکائی ہے۔"},"source":{"kind":"parcha-original"},"status":"sample","exam":"matric"},{"id":"matric-phy10-shm-03","v":1,"subject":"physics-10","chapter":"simple-harmonic-motion-and-waves","difficulty":2,"stem":"In simple harmonic motion, the acceleration of the body is:","options":["Constant","Directly proportional to displacement and opposite to it","Inversely proportional to displacement","Always zero"],"answer":1,"explain":{"en":"SHM is defined by a = −(constant) × x: acceleration is proportional to displacement from the mean position and always directed towards it. It is greatest at the extremes and zero at the mean position.","ur":"SHM کی تعریف a = −(مستقل) × x ہے: اسراع اوسط مقام سے ہٹاؤ کے متناسب اور ہمیشہ اسی کی طرف ہوتا ہے۔ یہ انتہائی مقام پر زیادہ اور اوسط مقام پر صفر ہوتا ہے۔"},"source":{"kind":"parcha-original"},"status":"sample","exam":"matric"},{"id":"matric-phy10-shm-04","v":1,"subject":"physics-10","chapter":"simple-harmonic-motion-and-waves","difficulty":1,"stem":"Waves transfer:","options":["Matter only","Both matter and energy","Neither matter nor energy","Energy, without carrying matter along"],"answer":3,"explain":{"en":"In a wave, the particles of the medium only vibrate about their positions; it is the energy that travels onward. A floating leaf bobs up and down as water waves pass but does not travel with them.","ur":"لہر میں واسطے کے ذرات صرف اپنی جگہ پر ارتعاش کرتے ہیں؛ آگے توانائی جاتی ہے۔ پانی پر تیرتا پتا لہروں کے گزرنے پر اوپر نیچے ہوتا ہے مگر ساتھ نہیں جاتا۔"},"source":{"kind":"parcha-original"},"status":"sample","exam":"matric"},{"id":"matric-phy10-shm-05","v":1,"subject":"physics-10","chapter":"simple-harmonic-motion-and-waves","difficulty":1,"stem":"Sound waves travelling through air are:","options":["Transverse waves","Electromagnetic waves","Longitudinal waves","Stationary waves"],"answer":2,"explain":{"en":"Air particles vibrate back and forth along the direction the sound travels, forming compressions and rarefactions: longitudinal waves. Sound needs a medium; electromagnetic waves do not.","ur":"ہوا کے ذرات آواز کی سمت میں آگے پیچھے ارتعاش کرتے ہیں اور دباؤ اور پھیلاؤ کے حصے بناتے ہیں: طولی لہریں۔ آواز کو واسطہ چاہیے۔"},"source":{"kind":"parcha-original"},"status":"sample","exam":"matric"},{"id":"matric-phy10-shm-06","v":1,"subject":"physics-10","chapter":"simple-harmonic-motion-and-waves","difficulty":2,"stem":"A wave has a frequency of 50 Hz and a wavelength of 2 m. Its speed is:","options":["25 m/s","100 m/s","52 m/s","0.04 m/s"],"answer":1,"explain":{"en":"v = fλ = 50 × 2 = 100 m/s.","ur":"v = fλ = 50 × 2 = 100 m/s۔"},"source":{"kind":"parcha-original"},"status":"sample","exam":"matric"},{"id":"matric-phy10-sound-01","v":1,"subject":"physics-10","chapter":"sound","seed":true,"difficulty":1,"stem":"Sound travels fastest in:","options":["Steel","Water","Air","A vacuum"],"answer":0,"explain":{"en":"Sound is fastest in solids, slower in liquids and slowest in gases: roughly 5,000 m/s in steel, 1,500 m/s in water and 340 m/s in air. It cannot travel through a vacuum at all.","ur":"آواز ٹھوس میں سب سے تیز، مائع میں کم اور گیس میں سب سے آہستہ چلتی ہے: اسٹیل میں تقریباً 5,000، پانی میں 1,500 اور ہوا میں 340 m/s۔ خلا میں آواز نہیں چلتی۔"},"source":{"kind":"parcha-original"},"status":"sample","exam":"matric"},{"id":"matric-phy10-sound-02","v":1,"subject":"physics-10","chapter":"sound","difficulty":1,"stem":"The audible frequency range for a normal human ear is about:","options":["2 Hz to 2,000 Hz","200 Hz to 200,000 Hz","20 Hz to 20,000 Hz","0 Hz to 2 Hz"],"answer":2,"explain":{"en":"People with normal hearing hear about 20 Hz to 20,000 Hz (20 kHz). Below 20 Hz is infrasound; above 20 kHz is ultrasound.","ur":"عام انسان تقریباً 20 Hz سے 20,000 Hz تک سنتا ہے۔ 20 Hz سے کم انفراساؤنڈ اور 20 kHz سے زیادہ الٹراساؤنڈ کہلاتی ہے۔"},"source":{"kind":"parcha-original"},"status":"sample","exam":"matric"},{"id":"matric-phy10-sound-03","v":1,"subject":"physics-10","chapter":"sound","difficulty":1,"stem":"Ultrasound has frequencies:","options":["Below 20 Hz","Between 20 Hz and 2,000 Hz","Exactly 20 kHz","Above 20 kHz"],"answer":3,"explain":{"en":"Ultrasound is sound above the upper limit of human hearing, 20 kHz. It is used in medical scans, cleaning and sonar.","ur":"الٹراساؤنڈ وہ آواز ہے جو انسانی سماعت کی بالائی حد 20 kHz سے اوپر ہو۔ یہ طبی اسکین، صفائی اور سونار میں استعمال ہوتی ہے۔"},"source":{"kind":"parcha-original"},"status":"sample","exam":"matric"},{"id":"matric-phy10-sound-04","v":1,"subject":"physics-10","chapter":"sound","difficulty":2,"stem":"The loudness of a sound depends mainly on its:","options":["Frequency","Amplitude","Wavelength alone","Speed"],"answer":1,"explain":{"en":"A larger amplitude carries more energy, so the sound is louder. Frequency decides the pitch, not the loudness.","ur":"زیادہ ایمپلیٹیوڈ زیادہ توانائی لے جاتا ہے، اس لیے آواز اونچی ہوتی ہے۔ فریکوئنسی پچ طے کرتی ہے، بلندی نہیں۔"},"source":{"kind":"parcha-original"},"status":"sample","exam":"matric"},{"id":"matric-phy10-sound-05","v":1,"subject":"physics-10","chapter":"sound","difficulty":1,"stem":"The pitch of a sound depends on its:","options":["Frequency","Amplitude","Loudness","Quality"],"answer":0,"explain":{"en":"Higher frequency means higher pitch: a whistle sounds shrill because of its high frequency. Amplitude affects loudness, and the mix of overtones gives quality (timbre).","ur":"زیادہ فریکوئنسی کا مطلب اونچی پچ ہے: سیٹی کی آواز تیز اسی لیے لگتی ہے۔ ایمپلیٹیوڈ بلندی اور اوور ٹونز آواز کی کوالٹی طے کرتے ہیں۔"},"source":{"kind":"parcha-original"},"status":"sample","exam":"matric"},{"id":"matric-phy10-sound-06","v":1,"subject":"physics-10","chapter":"sound","difficulty":3,"stem":"To hear a distinct echo in air (speed of sound 340 m/s), the reflecting surface must be at least about how far away?","options":["34 m","10 m","17 m","170 m"],"answer":2,"explain":{"en":"The ear keeps a sound for about 0.1 s, so the echo must return after at least 0.1 s. In 0.1 s sound travels 340 × 0.1 = 34 m there and back, so the surface must be at least 17 m away.","ur":"کان آواز کو تقریباً 0.1 s تک محسوس کرتا ہے، اس لیے بازگشت کم از کم 0.1 s بعد آنی چاہیے۔ اس وقت میں آواز آنا جانا 34 m طے کرتی ہے، یعنی دیوار کم از کم 17 m دور ہو۔"},"source":{"kind":"parcha-original"},"status":"sample","exam":"matric"}]}