A symbolic general strike declared by Poland's suspended Solidarity trade union met with partial success today as workers, students, and some motorists joined in the first nationally coordinated protest of martial law.

Official and unofficial reports indicated that strikes of up to 15 minutes had taken place at many major industrial plants around the country including the Lenin Shipyard in Gdansk, where Solidarity was born in August 1980. Students at several universities interrupted lectures and staged silent demonstrations on campuses.

The strike was called by a four-member provisional coordinating commission of underground Solidarity leaders to mark the passing of five months since the imposition of martial law last Dec. 13. Solidarity leaflets and bulletins had appealed to workers to stop work for 15 minutes at noon and for drivers to sound horns and stop their cars.

While reliable information from towns outside Warsaw was difficult to gather, reports indicated that the protests were more widespread than at any time since last December, suggesting that although resistance to martial law may be weak and disjointed, it is growing rather than diminishing.

Although not as outwardly dramatic as the Solidarity marches earlier this month, today's protests were potentially more significant. It is widely accepted here that any effective challenge to the military government that might force it in the direction of a compromise with Solidarity can only come from workers in the large factories.

During the first days of martial law, several hundred occupation strikes in factories and coal mines were broken up by riot police. Since then, there have been numerous reports of token strikes--but no coordinated protest action.

The authorities attempted to head off today's strikes and street protests with a major security and propaganda counteroffensive. For several days, workers were warned of the penalties under martial law for taking part in illegal strikes. Thousands of riot police, supported by water cannons and armored personnel carriers, patrolled the streets of Warsaw and other Polish cities.

A confidential circular designed by Deputy Premier Andrzej Jedynak instructed government ministries and factory directors to enforce strictly the martial-law decrees. Workers were told that they risked immediate dismissal and up to five years' imprisonment for organizing or participating in a strike.

Nevertheless, at Warsaw's central traffic circle on Marszalkowska Street today, several thousand passers-by joined in an impromptu demonstration of support of Solidarity. There were shouts of "We will win" and "Free Lech Walesa," the detained Solidarity leader. Many people thrust up their hands in victory signs, and there was loud applause for motorists and bus drivers who sounded their horns.

After 20 minutes, the demonstrators were dispersed peacefully by reinforcements of riot police who moved in with glass helmets down and clubs out. Elsewhere in Warsaw, and in other Polish cities, there was little response to Solidarity's call for traffic to halt.

Government spokesmen promptly labeled the protests "a failure" and claimed that work continued normally almost everywhere in the country. A commentary by the official news agency PAP said the lack of street disturbances illustrated "the maturity of Polish society" and its refusal to be swayed by "Western propaganda."

Later, however, Polish radio admitted that there had been scattered strikes throughout the country. The evening news bulletin, while presenting a picture of general calm, carried a list of more than a dozen towns or cities where there had been "isolated work stoppages" from Tychy and Nowy Sacz in the south to Wroclaw and Poznan in the west and Bydgoszcz and Gdansk in the north.

In Warsaw, foreign correspondents were able to confirm that protests of one form or another had taken place in many large factories including the giant steelworks, the FSO car factory, the Ursus tractor plant, the Polfa pharmaceutical firm, and the Rosa Luxemburg lamp plant. Participation varied from one factory or department to another, but, generally, a clear majority of workers appeared to be supporting the strike.

Underground Solidarity leaders had called on their supporters earlier not to take part in "unauthorized" protests. This evening, however, several hundred youths clashed with riot police in the old quarter of Warsaw following a mass in St. John's Cathedral.

Some of the youths were beaten outside the cathedral after they taunted police with shouts of "Gestapo." Tussles broke out when the police attempted to make some arrests and let off "noise bombs" nearby. The youths finally dispersed after a priest pleaded with them to go home.

Otherwise, most protests seemed to end peacefully. PAP reported that, following the demonstration in Marszalkowska Street, 49 drivers had their permits confiscated and the license plates of other cars that sounded their horns were noted down by police officers.

"All of them will be prosecuted," the news agency said.

At Warsaw University, about 5,000 students filed out of lecture rooms at noon and stood in silent groups in the main courtyard. Riot police were drawn up near the campus but did not interfere.

Eyewitnesses reported similar protests at the polytechnic institute in Warsaw and Gdansk, and Polish radio said "100 students" staged a peaceful protest at the Jagellonian University in Krakow.

At the FSO car plant in Warsaw, several hundred workers marched on the management building after the change of shift this afternoon. There were chants of "long live Solidarity," and the crowd sang the national anthem. It dispersed after police reinforcements were called up.

Some workers said Solidarity was still far too weak to mount an effective national protest of the kind it staged last year. "Everybody protests in his own way. The union isn't divided into factions, it's divided into individuals," remarked a worker from a Warsaw optics factory.

A reliable source in Gdansk quoted workers at the Lenin Shipyard there as saying they had joined the strike at noon. The workers also said they had been refusing to eat at the shipyard canteen for the past three days.