user67081: This is a basic level lazer alarm project. When anyone crosed or kept their hands on the lazer. buzzer starts working but when they took their hand from lazer light buzzer stops. But i want even after taking hands my buzzer should work for few (15-30) seconds .so please help me by giving idea..

user67324: If you are using a digital buzzer, you can do:
digitalWrite(buzzerPin,HIGH); 
delay(1000);
digitalWrite(buzzerPin,LOW);


67081: <p>This is a basic level lazer alarm project. When anyone crosed or kept their hands on the lazer. buzzer starts working but when they took their hand from lazer light buzzer stops. But i want even after taking hands my buzzer should work for few (15-30) seconds .so please help me by giving idea..</p>
 67324: <p>If you are using a digital buzzer, you can do:</p>
<pre><code>digitalWrite(buzzerPin,HIGH); 
delay(1000);
digitalWrite(buzzerPin,LOW);
</code></pre>
