Đề ôn thi Đề thi vào lớp 10 Trường THPT Chuyên KHXH môn Tiếng Anh - Mã đề KHXH-160

Lifting heavy objects (35) __________ a common challenge in engineering and construction. Simple machines were invented to help humans overcome such difficulties. One of the most ingenious of these devices is the pulley, a tool designed to redirect or multiply force, making it possible to move weights that would otherwise be impossible for a single person to handle.

A simple pulley consists (36) __________ a grooved wheel rotating around an axle. A rope runs along this groove. This setup allows you to change the direction of a force. For example, instead of pushing a heavy box up a ramp, you can pull down on a rope, which is often a more convenient motion for the human body. The system needs a fixed anchor point, a location (37) __________ the pulley can be securely attached.

While a single pulley is useful, the true power of this invention is revealed in compound systems. By adding more wheels to the system, the amount of force needed to lift an object is dramatically reduced. A system with two pulleys can make an object feel like it weighs half as much. Adding even more pulleys makes the task (38) __________ easier, although the mechanism becomes more complex.

Using a compound system is not without its trade-offs. (39) __________ the task becomes easier in terms of force, you must pull a greater length of rope. For example, if a system halves the required force, you must pull twice the amount of rope to lift the object one meter. There are (40) __________ different configurations, but all of them follow this rule. This is a fundamental (41) __________ of physics known as the conservation of energy.

Today, engineers use these concepts to design massive cranes and elevators. These complex machines are essentially advanced pulley systems, allowing them to (42) __________ enormous force to lift steel beams, shipping containers, and other heavy materials. From simple flagpoles to complex construction equipment, the humble pulley remains an essential tool in our modern world.

Imagine standing at the base of the Eiffel Tower in Paris, or exploring the ancient ruins of Machu Picchu in Peru, all without leaving your living room in Hanoi. This is the promise of Virtual Reality (VR) travel. As technology advances, especially with Vietnamese companies like FPT and Vingroup investing heavily in innovation, VR headsets are becoming more powerful and accessible. They offer a window to the world that was once pure science fiction. But as this technology becomes more common for your generation, a critical question arises: can a digital journey ever truly replace the experience of being there?

The arguments for VR travel are compelling. Firstly, it offers unprecedented accessibility. People with physical disabilities, tight budgets, or demanding schedules can 'visit' places they might never see otherwise. A student in a rural province could take a virtual field trip to the War Remnants Museum in Ho Chi Minh City. Secondly, VR provides a safe and controlled environment. There are no worries about lost luggage, language barriers, or tourist scams. The experience is curated and predictable. Finally, the educational potential is enormous. A history lesson becomes far more engaging when you can walk through an immersive digital recreation of ancient Rome.

However, critics argue that VR misses the very soul of travel. A real trip is a multi-sensory adventure. A VR headset can show you the bustling streets of Bangkok, but it cannot replicate the smell of street food, the humidity in the air, or the taste of a fresh mango smoothie. More importantly, travel is about spontaneous human connection—the unexpected conversation with a local shopkeeper, the shared smile with another traveler, or even the challenge of navigating a new city. The real experience, with all its imperfections, is something a programmed simulation cannot yet offer. A simulation lacks the unpredictability that makes travel so memorable, and you cannot truly understand a culture without it.

So, where does that leave us? It seems VR travel is not a question of 'either/or' but 'both/and'. It is not destined to be a replacement for real travel, but a powerful supplement. For example, a tourist could use VR to 'preview' potential destinations before booking an expensive flight, helping them make a more informed decision. Someone could also use it to 're-visit' a cherished holiday spot, bringing back fond memories. For Vietnamese youth, who are growing up surrounded by rapid technological change, understanding this balance is key.

In conclusion, while a VR headset can provide a stunning and educational glimpse of the world, it cannot capture the authentic, messy, and beautiful reality of travel. The magic of a real journey lies not just in what you see, but in the unexpected moments, the personal connections, and the full sensory experience. VR is an incredible tool that complements our ability to explore, but the passport and the backpack are not becoming obsolete just yet.