Đề ôn thi Đề thi vào lớp 10 Trường Phổ thông Năng khiếu môn Tiếng Anh - Mã đề PTNK-40

Lifting heavy objects (21) __________ 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 (22) __________ 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 (23) __________ 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 significantly easier, although the mechanism becomes more complex.

Using a compound system is not without its trade-offs. Although 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 (24) __________ different configurations, but all of them follow this rule. This is a fundamental principle 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 exert 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.

The digital age reshaped how we connect, making it easier to find people who share our unique passions. No longer limited by geography, individuals with niche interests locate their "tribe"—a community of like-minded souls worldwide. These online spaces offer a profound sense of belonging. From discussing hobbies to sharing knowledge, the internet provides a platform for building supportive networks, transforming solitary pursuits into collective experiences. This global connectivity allows diverse voices to converge, creating vibrant ecosystems where shared enthusiasm flourishes beyond traditional boundaries. [I]

The power of these online groups lies in fostering genuine connection and mutual support. Whether you're a budding artist seeking feedback, a programmer troubleshooting code, or simply passionate about a specific music genre, these communities offer a forum for learning, encouragement, and camaraderie. Members often share advice, celebrate successes, and offer comfort during challenges, creating environments where individuals feel seen and valued. This sense of shared identity strengthens bonds that transcend physical distance, making difficult experiences more manageable and joys more profound. [II]

This phenomenon resonates strongly in Vietnam, where online groups are an integral part of daily life and social interaction. Platforms like Facebook brim with communities for every imaginable hobby. For example, 'Hội Thích Trồng Cây' (Plant Lovers Association) allows enthusiasts to exchange plant care tips, share photos, and even trade rare species. Similarly, vibrant fan clubs for local football teams, K-Pop idols, or artists thrive, providing spaces for fans to discuss news, organize meetups, and express collective devotion, highlighting the social fabric woven through digital connections.

For young people aged 14-15, digital communities are particularly relevant and often indispensable. You are likely already a member, perhaps connecting with fellow gamers to strategize, joining study groups for academic support, or discussing your favorite TV show or musical artist. These spaces offer an outlet for self-expression, a platform to explore interests deeply, and emotional support during challenging times, like preparing for exams or navigating social pressures. They validate individual passions and foster belonging, proving digital bonds can be as meaningful as offline ones. [III]

While finding your tribe online offers numerous benefits, it’s important to navigate these spaces thoughtfully. Being mindful of screen time, verifying information, and practicing good digital citizenship are crucial for a positive experience. [IV] They remind us that even in a vast world, shared interests can bring us together, proving the search for belonging often leads us to unexpected, supportive digital homes.